xResource::withoutWrapping() should not affect JsonResource superclass

[BrianHenryIE]

Where class ContributorResource extends JsonResource, calling the ContributorResource::withoutWrapping() is really calling JsonResource::withoutWrapping() which was then setting the public static $wrap of JsonResource to null, rather than acting on the subclass.

By adding the property to each subclass, calling :withoutWrapping() changes the property only on the subclass and not on the super class.

[BrianHenryIE]

Hey. I ran pint before submitting the PR. The workflow action failure seems unrelated:

[MohmmedAshraf]

Hey @BrianHenryIE thank you for the PR currently am working on some features and refactor some parts of the code i will merge this soon

[MohmmedAshraf]

Thank you @BrianHenryIE