Add support for v3 app and space endpoints for metadata (labels and annotations)

[checketts]

Fixes #1027 and contributes to #946

I'm new to this library so I've create the request/response and matching tests.

[linux-foundation-easycla]

The committers are authorized under a signed CLA.

• ✅ checketts (f443875)

[checketts]

I submitted the CLA

[twoseat]

Hi @checketts I've working on the code now and aside from some formatting etc. all looks good. Unfortunately it kills our integration test platform (because our test cleanup doesn't yet have a way to delete the metadata your tests quite rightly create). But it is in progress!

[checketts]

Thanks for the update!

Anything I can do to help with the integration tests? Or is it breaking un-related integration tests?

[twoseat]

The problem, which I imagine you may find yourself hitting at some point, is that neither the v2 nor v3 delete-space endpoints currently support deleting spaces with associated metadata. And as our integration test suite cleans up everything after each run that's a problem! I'm going to temporarily fix it by cleaning the metadata first until space deletion is properly supported.

Let me know if you think I'm wrong!