Composer: raise minimum PHPUnit 8 version to 8.4.0

... to allow for a simplification in the test suite.

Author: jrfnl

composer.json

@@ -36,7 +36,7 @@
         "ext-xmlwriter": "*"
     },
     "require-dev": {
-        "phpunit/phpunit": "^8.0 || ^9.3.4 || ^10.5.32 || 11.3.3 - 11.5.28 || ^11.5.31"
+        "phpunit/phpunit": "^8.4.0 || ^9.3.4 || ^10.5.32 || 11.3.3 - 11.5.28 || ^11.5.31"
     },
     "bin": [
         "bin/phpcbf",

tests/Core/Ruleset/AbstractRulesetTestCase.php

@@ -73,22 +73,15 @@ protected function expectRuntimeExceptionMessage($message)
 
 
     /**
-     * Helper method to tell PHPUnit to expect a PHPCS RuntimeException which matches a regex patten
-     * in a PHPUnit cross-version compatible manner.
+     * Helper method to tell PHPUnit to expect a PHPCS RuntimeException which matches a regex pattern.
      *
      * @param string $regex The regex which should match.
      *
      * @return void
      */
     protected function expectRuntimeExceptionRegex($regex)
     {
-        if (method_exists($this, 'expectExceptionMessageMatches') === true) {
-            $this->expectException(RuntimeException::class);
-            $this->expectExceptionMessageMatches($regex);
-        } else {
-            // PHPUnit < 8.4.0.
-            $this->expectException(RuntimeException::class);
-            $this->expectExceptionMessageRegExp($regex);
-        }
+        $this->expectException(RuntimeException::class);
+        $this->expectExceptionMessageMatches($regex);
     }
 }