bug #38094 [PhpUnitBridge] Skip internal classes in CoverageListenerTrait (sanmai)

This PR was squashed before being merged into the 4.4 branch.

Discussion
----------

[PhpUnitBridge] Skip internal classes in CoverageListenerTrait

PHPUnit 9+ is picky about test covering, say, a `\RuntimeException`. Fails with the likes:

    "@covers RuntimeException" is invalid

Judging by the commit e06850c12b this change is required for PHPUnit 9.1 and up. [Here's it being tested.](60c6fb972b/tests/unit/ClassMethodUnitTest.php (L49-L54))

| Q             | A
| ------------- | ---
| Branch?       | 4.4
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Tickets       | Follow-up to #38054
| License       | MIT

Commits
-------

a0dedb9aa6 [PhpUnitBridge] Skip internal classes in CoverageListenerTrait

src/Symfony/Bridge/PhpUnit/Legacy/CoverageListenerTrait.php

@@ -107,6 +107,13 @@ class CoverageListenerTrait
         $symbolAnnotations = new \ReflectionProperty($docBlock, 'symbolAnnotations');
         $symbolAnnotations->setAccessible(true);
 
+        // Exclude internal classes; PHPUnit 9.1+ is picky about tests covering, say, a \RuntimeException
+        $covers = array_filter($covers, function ($class) {
+            $reflector = new ReflectionClass($class);
+
+            return $reflector->isUserDefined();
+        });
+
         $symbolAnnotations->setValue($docBlock, array_replace($docBlock->symbolAnnotations(), [
             'covers' => $covers,
         ]));