bug symfony#53239 [HttpKernel] fix "Cannot redeclare renderSymfonyLogoSvg()" inside phpunit tests (davidesigner)

This PR was merged into the 7.0 branch.

Discussion
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[HttpKernel] fix "Cannot redeclare renderSymfonyLogoSvg()" inside phpunit tests

| Q             | A
| ------------- | ---
| Branch?       | 7.0
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Issues        | N/A
| License       | MIT

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In a PHPUnit test case with dataProvider, there was a fatal error:

> Compile Error: Cannot redeclare renderSymfonyLogoSvg() (previously declared in /vendor/symfony/http-kernel/Resources/welcome.html.php:219) (500 Internal Server Error)

This include_once fix the error.

Commits
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ac97c9b [HttpKernel] fix "Cannot redeclare renderSymfonyLogoSvg()" inside phpunit tests

Author: fabpot

src/Symfony/Component/HttpKernel/EventListener/RouterListener.php

@@ -159,7 +159,7 @@ private function createWelcomeResponse(): Response
         $docVersion = substr(Kernel::VERSION, 0, 3);
 
         ob_start();
-        include \dirname(__DIR__).'/Resources/welcome.html.php';
+        include_once \dirname(__DIR__).'/Resources/welcome.html.php';
 
         return new Response(ob_get_clean(), Response::HTTP_NOT_FOUND);
     }