[php-symfony] fix sequencial escape when validating a class type

[Fl0ux]

In the api controller, validation is done using doubles quotes to check class type. This can lead to errors by interpreting a part of the string as an escaped character.

For exemple, if it compares class name like this one "\My\Namespace\Xcase", "\Xca" will be interpreted as an hexadecimal character and the validator will not match the class.
See https://www.php.net/manual/en/regexp.reference.escape.php for more informations.

Using single quotes fix the problem as strings are not interpreted as escaped ones.

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@jebentier, @dkarlovi, @mandrean, @jfastnacht, @ybelenko, @renepardon

---

Summary by cubic

Switch Assert\Type strings to single quotes in the PHP Symfony generator to prevent PHP escape-sequence interpretation during class type validation. Regenerated Symfony samples; added a missing return type in the test AppKernel.

• Bug Fixes
  • Updated api_input_validation.mustache to use single quotes for non-enum types (models and primitives).
  • Prevents misvalidation when class names include backslashes that could be read as escapes (e.g., "\Xca").

^{Written for commit c57b655. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 4 files

[wing328]

thanks for the PR

can you please review the build failure when you've time?

[wing328]

Thanks for the PR but your commit (as shown in the Commits tab) is not linked to your Github account, which means this PR won't count as your contribution in https://github.com/OpenAPITools/openapi-generator/graphs/contributors.

Let me know if you need help fixing it.

Ref: https://github.com/OpenAPITools/openapi-generator/wiki/FAQ#how-can-i-update-commits-that-are-not-linked-to-my-github-account
Thanks for the PR but your commit (as shown in the Commits tab) is not linked to your Github account, which means this PR won't count as your contribution in https://github.com/OpenAPITools/openapi-generator/graphs/contributors.

Let me know if you need help fixing it.

Ref: https://github.com/OpenAPITools/openapi-generator/wiki/FAQ#how-can-i-update-commits-that-are-not-linked-to-my-github-account