Circuit.contributions should contain list of contributions

[chr-pok]

Description:
Let's assume we are fetching a circuit with circuit = client.get_entity(entity_id="<ID>", entity_type=models.Circuit). Currently, the resulting circuit.contributions (which is derived from Entity) returns always None but should contain the actual list of contributions that have been registered, which can be retrieved by contributions = client.search_entity(entity_type=models.Contribution, query={"entity__id": circuit.id}).all().

This may require a (small) change in entitycore/app/service/circuit.py.

Acceptance criterion:
For a fetched circuit, circuit.contributions contains the list of contributions.

[eleftherioszisis]

Should be fixed in staging. @chr-pok could you please verify?

[chr-pok]

Yes, it works! Thanks for fixing it so quickly!