CI: test postgis driver

[pjonsson]

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📚 Documentation preview 📚: https://datacube-ows--1138.org.readthedocs.build/en/1138/

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 93.14%. Comparing base (23ce3c6) to head (b9c8f4f).
Report is 176 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #1138   +/-   ##
========================================
  Coverage    93.14%   93.14%           
========================================
  Files           53       53           
  Lines         7193     7193           
========================================
  Hits          6700     6700           
  Misses         493      493           

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[pjonsson]

This should be fixed by opendatacube/datacube-core#1782.

[SpacemanPaul]

I approve of what you are trying to do here, but you are only fixing half the problem.

I need to look at a few other things first, but will probably close this PR unmerged and replace it with a more comprehensive PR.

[SpacemanPaul]

Replaced by #1139

[pjonsson]

Replaced by #1139

@SpacemanPaul I feel you need to explain things a bit. As far as I can tell, this PR adds test coverage for the different GetCapabilities and Prometheus metrics when using the new postgis index driver instead of the legacy postgres index driver. I disabled the ping test for postgis index driver because that failed at the time of making this PR.

The PR you linked makes ping multi-db-aware, which is great, but even if that is then covered by some existing test, that is still only 20% of what this PR adds (?) testing of.

I'm not against unit tests, but even with a well-maintained test suite of unit tests, my experience is that end-to-end testing like this one still tends to catch bugs that were not found by the unit tests.