[PHP] Fix deprecations in PHP 8.1

[satackey]

Fixed the following deprecations in PHP 8.1. This pull request resolves #11742.

Deprecated: Return type of XXXX::offsetExists($offset) should either be compatible with ArrayAccess::offsetExists(mixed $offset): bool, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in ...

Added the #[\ReturnTypeWillChange] attribute or the same type hint as the internal interface to the return value of methods that implement PHP's internal interface ArrayAccess.

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  @jebentier (2017/07), @dkarlovi (2017/07), @mandrean (2017/08), @jfastnacht (2017/09), @ackintosh (2017/09) ❤️, @ybelenko (2018/07), @renepardon (2018/12)

[ksvirkou-hubspot]

Hi Everyone
It is really important changes
Could anyone check it please?
@jebentier @dkarlovi @mandrean @jfastnacht @ackintosh @ybelenko @renepardon

[ksvirkou-hubspot]

Hi Everyone
Any updates ?
@jebentier @dkarlovi @mandrean @jfastnacht @ackintosh @ybelenko @renepardon
@wing328

[ybelenko]

Gonna take care of it tomorrow. Sorry, too much daytime work. I want to pay maximum attention to all php based generators in the March. Next major release with breaking changes scheduled to the end of the month, I will have to wait for a year to add significant changes if I miss that deadline. Crazy. Thanks for patience.

[ybelenko]

You don't use mixed type(accepted in PHP 8) to make it compatible with PHP 7.4, am I right?

[satackey]

Yes. PHP 7.4 is in the security support period, so I thought we shouldn't make breaking changes until it goes EOL.

[ybelenko]

@satackey You didn't test your own PR? Should at least mention that, we don't always check PRs locally. It's a luck that I noticed boolean typehint from a brief look.

[satackey]

@ybelenko I used this code that creates an instance of the object for testing and confirmed that the deprecation notice disappears, I hadn't tested it to cover the change.
Thank you for your review. I appreciate it.

[ybelenko]

Just checked locally under PHP 7.4, 8.0 and 8.1. Works without notices or errors across versions.