In the spirit of being DRY and making common methods reusable. The recently added getValidRequestBody should be moved out of each client implementation into a the client-core utils file.

• Refactor the angular, fetch, axios, and next clients to import and implement the getValidRequestBody method.
• Add tests
• Existing tests should continue to pass
• Update snapshots

Related to changes introduced: #2564, #2600

I will submit a PR for this change.