HMS-5530: add a helper for cleaning up test resources

[dominikvagner]

Summary

This adds a new helper for cleaning up test resources and a way to use it our API client fixture for pre-test and post-test cleaning up.

Currently this PR includes a dummy test file (`Test.spec.ts`) which is to be deleted, but now 
shows off two ways of approaching cleanups in our test, which should help us make them idempotent. 
Both of these approaches result in the same thing, stuff gets cleaned up pre+post test.
What would you wanna use more? 💭 
Let's vote (on the PR desc): 
- 🚀 = Approach no. 1
- 👀 = Approach no. 2

[jlsherrill]

https://issues.redhat.com/browse/HMS-5530