Support new JWT token based auth (openEO API 1.3.0)

[niebl]

#850

Includes:

• checking conformance in connection.authenticate_basic() and connection.authenticate_oidc() and formatting the bearer tokens accordingly
• a /conformance endpoint in DummyBackend and a has_conformance({url}) method in capabilities. So JWT bearer token conformance can be checked.

[niebl]

still WIP, as testing with JWT conformant backends is not yet implemented (manual tests have shown that there is still something going wrong though)

[soxofaan]

hmm, it seems this PR got in a bad state, making the signal/noise ratio bad for review. I see various changes in places that are unrelated to the feature to implement here (conversions.py, results.py, _version.py, metadata.py, test_s3sts.py, ...)

did you by any chance cherry-picked commits from master, instead of merging master?

[m-mohr]

@soxofaan I did clean up a potentially failed merge, this should improve the situation.

Somehat related: We also have changes come in from the linter for some of those files each time we run the linter. It might be that master is not clean with regards to linting?! => #869

[soxofaan]

sorry for delay, I finally found some time to give this another review

[soxofaan]

and another thing: this deserves a mention in the changelog too

[niebl]

Thank you very much for the review. I am sorry for the delay. I will be able to work on that feedback now

[niebl]

@soxofaan thank you for the review. I was able to apply your suggestions and shrink the size of the PR a little. I am once again sorry for the delay