fix(doctrine): resource_class from context instead of entity class

[KaiGrassnick]

…default to old behavior of using entityClass

Q	A
Branch?	3.3
Tickets	Closes #6590
License	MIT
Doc PR

This PR fixes the issue stated in #6590. In case of an Entity API Resource everything worked as expected, when using an DTO API Resource with stateOptions set to an Entity one would run into an Runtime Exception, as the LinksHandler could not fetch the Entity from the API Resource.

This could be fixed, by using the resource_class instead of the EntityClass from the EntityManager.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[soyuka]

Stale bot made me look at this again, we may need to fix this and/or at least merge your tests, could you take a look at my comment? Thanks!

[NicoDPA]

Hi, I'm looking for this bug because I use the DTO approach with Graphql