diff --git a/core/drupalci.yml b/core/drupalci.yml
index cd92d8102d..de77eb626e 100644
--- a/core/drupalci.yml
+++ b/core/drupalci.yml
@@ -3,49 +3,15 @@
 # https://www.drupal.org/drupalorg/docs/drupal-ci/customizing-drupalci-testing
 _phpunit_testgroups_to_execute: &testgroups
   # Default: all of Drupal core's test suite runs.
-  testgroups: '--all'
+  testgroups: '--class "\Drupal\Tests\Component\Utility\RandomTest"'
   # Alternative: run only the tests for one particular module.
   # testgroups: '--module ckeditor5'
 build:
   assessment:
     testing:
-      # Run code quality checks.
-      container_command.commit-checks:
-        commands:
-          - "core/scripts/dev/commit-code-check.sh --drupalci"
-        halt-on-fail: true
-      # run_tests task is executed several times in order of performance speeds.
-      # halt-on-fail can be set on the run_tests tasks in order to fail fast.
-      # suppress-deprecations is false in order to be alerted to usages of
-      # deprecated code.
       run_tests.phpunit:
         types: 'PHPUnit-Unit'
         suppress-deprecations: false
         halt-on-fail: false
         <<: *testgroups
-      run_tests.kernel:
-        types: 'PHPUnit-Kernel'
-        suppress-deprecations: false
-        halt-on-fail: false
-        <<: *testgroups
-      run_tests.build:
-        # Limit concurrency due to disk space concerns.
-        concurrency: 15
-        types: 'PHPUnit-Build'
-        suppress-deprecations: false
-        halt-on-fail: false
-        <<: *testgroups
-      run_tests.functional:
-        types: 'PHPUnit-Functional'
-        suppress-deprecations: false
-        halt-on-fail: false
-        <<: *testgroups
-      run_tests.javascript:
-        concurrency: 15
-        types: 'PHPUnit-FunctionalJavascript'
-        suppress-deprecations: false
-        halt-on-fail: false
-        <<: *testgroups
-      # Run nightwatch testing.
-      # @see https://www.drupal.org/project/drupal/issues/2869825
-      nightwatchjs: {}
+        repeat: 5000
diff --git a/core/tests/Drupal/Tests/Component/Utility/RandomTest.php b/core/tests/Drupal/Tests/Component/Utility/RandomTest.php
index e1682b67f5..0110c7bdf4 100644
--- a/core/tests/Drupal/Tests/Component/Utility/RandomTest.php
+++ b/core/tests/Drupal/Tests/Component/Utility/RandomTest.php
@@ -23,98 +23,6 @@ class RandomTest extends TestCase {
    */
   protected $firstStringGenerated = '';
 
-  /**
-   * Tests unique random string generation.
-   *
-   * @covers ::string
-   */
-  public function testRandomStringUniqueness() {
-    $strings = [];
-    $random = new Random();
-    for ($i = 0; $i <= 50; $i++) {
-      $str = $random->string(1, TRUE);
-      $this->assertFalse(isset($strings[$str]), 'Generated duplicate random string ' . $str);
-      $strings[$str] = TRUE;
-    }
-  }
-
-  /**
-   * Tests unique random name generation.
-   *
-   * @covers ::name
-   */
-  public function testRandomNamesUniqueness() {
-    $names = [];
-    $random = new Random();
-    for ($i = 0; $i <= 10; $i++) {
-      $str = $random->name(1, TRUE);
-      $this->assertFalse(isset($names[$str]), 'Generated duplicate random name ' . $str);
-      $names[$str] = TRUE;
-    }
-  }
-
-  /**
-   * Tests infinite loop prevention whilst generating random names.
-   *
-   * @covers ::name
-   */
-  public function testRandomNameException() {
-    // There are fewer than 100 possibilities so an exception should occur to
-    // prevent infinite loops.
-    $random = new Random();
-    $this->expectException(\RuntimeException::class);
-    for ($i = 0; $i <= 100; $i++) {
-      $str = $random->name(1, TRUE);
-      $names[$str] = TRUE;
-    }
-  }
-
-  /**
-   * Tests infinite loop prevention whilst generating random strings.
-   *
-   * @covers ::string
-   */
-  public function testRandomStringException() {
-    // There are fewer than 100 possibilities so an exception should occur to
-    // prevent infinite loops.
-    $random = new Random();
-    $this->expectException(\RuntimeException::class);
-    for ($i = 0; $i <= 100; $i++) {
-      $str = $random->string(1, TRUE);
-      $names[$str] = TRUE;
-    }
-  }
-
-  /**
-   * Tests random name generation if uniqueness is not enforced.
-   *
-   * @covers ::name
-   */
-  public function testRandomNameNonUnique() {
-    // There are fewer than 100 possibilities if we were forcing uniqueness so
-    // exception would occur.
-    $random = new Random();
-    for ($i = 0; $i <= 100; $i++) {
-      $random->name(1);
-    }
-    $this->assertTrue(TRUE, 'No exception thrown when uniqueness is not enforced.');
-  }
-
-  /**
-   * Tests random string if uniqueness is not enforced.
-   *
-   * @covers ::string
-   */
-  public function testRandomStringNonUnique() {
-    // There are fewer than 100 possibilities if we were forcing uniqueness so
-    // exception would occur.
-    $random = new Random();
-    for ($i = 0; $i <= 100; $i++) {
-      $random->string(1);
-    }
-    $this->assertTrue(TRUE, 'No exception thrown when uniqueness is not enforced.');
-  }
-
   /**
    * Tests unique random name generation.
    *
@@ -130,103 +38,4 @@ public function testRandomMachineNamesUniqueness(): void {
     }
   }
 
-  /**
-   * Tests infinite loop prevention whilst generating random names.
-   *
-   * @covers ::machineName
-   */
-  public function testRandomMachineNameException(): void {
-    // There are fewer than 100 possibilities so an exception should occur to
-    // prevent infinite loops.
-    $this->expectException(\RuntimeException::class);
-    $random = new Random();
-    for ($i = 0; $i <= 100; $i++) {
-      $random->machineName(1, TRUE);
-    }
-  }
-
-  /**
-   * Tests random name generation if uniqueness is not enforced.
-   *
-   * @covers ::machineName
-   */
-  public function testRandomMachineNameNonUnique(): void {
-    // There are fewer than 100 possibilities meaning if uniqueness was
-    // enforced, there would be an exception.
-    $random = new Random();
-    for ($i = 0; $i <= 100; $i++) {
-      $random->machineName(1);
-    }
-    $this->expectNotToPerformAssertions();
-  }
-
-  /**
-   * Tests random object generation to ensure the expected number of properties.
-   *
-   * @covers ::object
-   */
-  public function testRandomObject() {
-    // For values of 0 and 1 \Drupal\Component\Utility\Random::object() will
-    // have different execution paths.
-    $random = new Random();
-    for ($i = 0; $i <= 1; $i++) {
-      $obj = $random->object($i);
-      $this->assertCount($i, get_object_vars($obj), 'Generated random object has expected number of properties');
-    }
-  }
-
-  /**
-   * Tests random string validation callbacks.
-   *
-   * @covers ::string
-   */
-  public function testRandomStringValidator() {
-    $random = new Random();
-    $this->firstStringGenerated = '';
-    $str = $random->string(1, TRUE, [$this, '_RandomStringValidate']);
-    $this->assertNotEquals($this->firstStringGenerated, $str);
-  }
-
-  /**
-   * Tests random word.
-   *
-   * @covers ::word
-   */
-  public function testRandomWordValidator() {
-    $random = new Random();
-    // Without a seed, test a different word is returned each time.
-    $this->firstStringGenerated = $random->word(5);
-    $next_str = $random->word(5);
-    $this->assertNotEquals($this->firstStringGenerated, $next_str);
-
-    // With a seed, test the same word is returned each time.
-    mt_srand(0);
-    $this->firstStringGenerated = $random->word(5);
-    mt_srand(0);
-    $next_str = $random->word(5);
-    $this->assertEquals($this->firstStringGenerated, $next_str);
-  }
-
-  /**
-   * Callback for random string validation.
-   *
-   * @see \Drupal\Component\Utility\Random::name()
-   * @see \Drupal\Tests\Component\Utility\RandomTest::testRandomStringValidator()
-   *
-   * @param string $string
-   *   The random string to validate.
-   *
-   * @return bool
-   *   TRUE if the random string is valid, FALSE if not.
-   */
-  public function _RandomStringValidate($string) {
-    // Return FALSE for the first generated string and any string that is the
-    // same, as the test expects a different string to be returned.
-    if (empty($this->firstStringGenerated) || $string == $this->firstStringGenerated) {
-      $this->firstStringGenerated = $string;
-      return FALSE;
-    }
-    return TRUE;
-  }
-
 }