[QA] Combine coreApi and apiX suites

[amrita-shrestha]

Describe the bug

Our API test folder includes two types of test suites: those prefixed with coreApiX, which contain transfer API tests migrated from the core repository and those prefixed with apiX, which include new tests specifically designed for oCIS. At present, there appears to be no need to differentiate these test suites by naming them coreApiX and apiX.

the word `coreApi` deceives us, tests in ocis both `apiX` and `coreApiX` are for the ocis server and not for the oc10. So, I don't see a reason not to add feature file there.

Originally posted by @saw-jan in #10170 (comment)

Considering the above comment, this issue has been created to merge the coreApi and api test suites that cover similar feature tests.

[saw-jan]

We should also think about the tests for reva-edge. How should we identify tests that run in reva? use skip tags to skip all apiX test suites (which we currently don't run in reva)?