diff --git a/core/modules/system/src/Tests/Session/SessionAuthenticationTest.php b/core/modules/system/src/Tests/Session/SessionAuthenticationTest.php
index ed3f6e8..31530a7 100644
--- a/core/modules/system/src/Tests/Session/SessionAuthenticationTest.php
+++ b/core/modules/system/src/Tests/Session/SessionAuthenticationTest.php
@@ -125,7 +125,7 @@ public function testBasicAuthNoSession() {
     // sustaining the session.
     $this->basicAuthGet($no_cookie_url, $this->user->getUsername(), $this->user->pass_raw);
     $this->assertResponse(200, 'The user is successfully authenticated using basic authentication.');
-    $this->assertFalse($this->drupalGetHeader('set-cookie', TRUE), 'No cookie is set on a route protected with basic authentication.');
+    $this->assertFalse($this->drupalGetHeader('set-cookie'), 'No cookie is set on a route protected with basic authentication.');
 
     // On the other hand, authenticating using Cookie sets a cookie.
     $edit = ['name' => $this->user->getUsername(), 'pass' => $this->user->pass_raw];