fix: Use normalisation context when none is provided in tests

[kevin-macquer-omnilog]

Q	A
Branch?	main
Tickets	Closes #6146
License	MIT
Doc PR

In #6098 the behavious was changed in the test trait.
Before when you didn't provide a serialization context, the SerializationFactory would initialize it to the normalization context of the operation.
With this change the normalization context is an empty array instead so we loose the normalization context.

Solution: use the normalization context of the operation if the serialization context is null.

[devzenfr]

I tested this change and that resolves the issues I had inside #6146. Thanks @kevin-macquer-omnilog, I hope this gets merged.

[kevin-macquer-omnilog]

The test that is failing here https://github.com/api-platform/core/actions/runs/7872836937/job/21481776163?pr=6157 is also failing on the main branch in my machine, it doesn't seems linked to those changes.

[soyuka]

we should target 3.2 also is it possible to add a non-reg test in the ApiTestCaseTest?

[kevin-macquer-omnilog]

we should target 3.2 also is it possible to add a non-reg test in the ApiTestCaseTest?

Hi soyuka, I'm working on the test today, will post an update when it's done.

[kevin-macquer-omnilog]

@soyuka I've added the required tests.
The test doesn't work on the main branch but work on this branch.

For targeting 3.2 it needs to be merged on the main branch right?

[kevin-macquer-omnilog]

@soyuka I've changed the target of this PR to 3.2.

[soyuka]

amazing !