minor symfony#57403 [PhpUnitBridge] Add missing import (HypeMC)

This PR was merged into the 5.4 branch.

Discussion
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[PhpUnitBridge] Add missing import

| Q             | A
| ------------- | ---
| Branch?       | 5.4
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Issues        | -
| License       | MIT

Follow up to symfony#57110, looks like I forgot to commit the use statement. 😞

Commits
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661e79a [PhpUnitBridge] Add missing import

Author: fabpot

src/Symfony/Bridge/PhpUnit/DeprecationErrorHandler.php

@@ -11,6 +11,7 @@
 
 namespace Symfony\Bridge\PhpUnit;
 
+use PHPUnit\Framework\TestCase;
 use PHPUnit\Framework\TestResult;
 use PHPUnit\Runner\ErrorHandler;
 use PHPUnit\Util\Error\Handler;