Upgrade to PHPUnit 11

[wouterj]

This PR upgrades to PHPUnit 11, including using it's deprecation handling features. Starting with PHPUnit 11, all deprecations features from the bridge are implemented in PHPUnit.

This PR also stops using the PhpunitBridge wrapper, which is recommended for applications in the documentation for at least the past 2 years.

I've added the configuration to make PHPUnit not report indirect deprecations (those caused by 3rd party code), and to fail on a test that triggers a direct deprecation. I think this is the most sensible default configuration that we should promote. If we agree, I'll create a recipe to do this automatically.

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This PR has mostly been created as a test to see what we need to fix in recipes/code and add to the documentation about PHPUnit 11.

[javiereguiluz]

Wouter, if you have some time, please try to rebase this PR so we can merge it. Thanks a lot!

[wouterj]

Rebased. The test seem to be broken in main though.

Also, I'm not sure on what the policies for this project are, but this PR is not in line with the Flex recipes for the phpunit configuration. I was thinking we first have to fix Flex before we could merge this?

[rosier]

The lines https://github.com/symfony/demo/blob/main/phpstan.dist.neon#L8-L10 can be removed.

This should fix the Lint / PHPStan test

[javiereguiluz]

Thanks Wouter 🙇🙇

Jan, I removed the lines while merging. Thanks.

[alexander-schranz]

As we do this in the demo I think we should adjust also the test-pack: symfony/test-pack#24

[coldic3]

This is no longer valid https://github.com/symfony/demo#tests

The bin/phpunit together with the symfony/phpunit-bridge package has been removed in this PR.