The GET/DEL endpoints of relations-api use query params (per REST) whereas POST uses post-data.

The query params and the post-data can be directly mapped.

Find or create some functionality for easily mapping between the two, allowing for easy re-use of data for GET/POST/DEL queries.

This will serve as a strong basis for writing easily reproducible and re-usable test-cases.

NOTE: This will likely wrap-up both RHCLOUD-34558 and RHCLOUD-34350