diff --git a/src/EventSubscriber/ConfigCacheInvalidator.php b/src/EventSubscriber/ConfigCacheInvalidator.php
index d85b190..58cea49 100644
--- a/src/EventSubscriber/ConfigCacheInvalidator.php
+++ b/src/EventSubscriber/ConfigCacheInvalidator.php
@@ -46,7 +46,7 @@ class ConfigCacheInvalidator implements EventSubscriberInterface {
   /**
    * {@inheritdoc}
    */
-  public static function getSubscribedEvents() {
+  public static function getSubscribedEvents(): array {
     $events[ConfigEvents::SAVE][] = ['onSave'];
     return $events;
   }
diff --git a/tests/src/Kernel/SubPathautoKernelTest.php b/tests/src/Kernel/SubPathautoKernelTest.php
index ec3efc0..5402de3 100644
--- a/tests/src/Kernel/SubPathautoKernelTest.php
+++ b/tests/src/Kernel/SubPathautoKernelTest.php
@@ -64,8 +64,6 @@ class SubPathautoKernelTest extends KernelTestBase {
    */
   protected function setUp(): void {
     parent::setUp();
-
-    $this->installSchema('system', 'sequences');
     $this->installEntitySchema('user');
     $this->installEntitySchema('node');
     $this->installEntitySchema('path_alias');
@@ -275,7 +273,7 @@ class SubPathautoKernelTest extends KernelTestBase {
    *   An array of test cases, each of which contains whether redirect is
    *   supported and the expected string.
    */
-  public function noRedirectSupportDataProvider(): array {
+  public static function noRedirectSupportDataProvider(): array {
     return [
       'redirect is supported' => [TRUE, '/node/1/edit'],
       'redirect is not supported' => [FALSE, '/foo/bar/edit'],