Upload coverage data from GitHub actions.

[Spacetown]

@latk Can we now remove appveyor tests? GCC5 is checked in Docker and Windows is checked with GCC-8.

[codecov]

Codecov Report

Merging #455 (bb80b50) into master (a51a7fe) will increase coverage by 0.45%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #455      +/-   ##
==========================================
+ Coverage   95.08%   95.53%   +0.45%     
==========================================
  Files          20       20              
  Lines        2420     2441      +21     
  Branches      418      418              
==========================================
+ Hits         2301     2332      +31     
+ Misses         54       48       -6     
+ Partials       65       61       -4     

Flag	Coverage Δ
ubuntu-18.04	95.03% <ø> (?)
windows-2019	95.12% <ø> (?)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
gcovr/tests/test_config.py	100.00% <0.00%> (ø)
gcovr/tests/test_gcov_parser.py	100.00% <0.00%> (ø)
gcovr/tests/test_html_generator.py	100.00% <0.00%> (ø)
gcovr/configuration.py	99.28% <0.00%> (+<0.01%)	⬆️
gcovr/workers.py	98.82% <0.00%> (+0.01%)	⬆️
gcovr/coverage.py	99.13% <0.00%> (+0.02%)	⬆️
gcovr/html_generator.py	96.98% <0.00%> (+0.08%)	⬆️
gcovr/gcov.py	87.94% <0.00%> (+0.58%)	⬆️
gcovr/tests/test_gcovr.py	92.94% <0.00%> (+0.69%)	⬆️
gcovr/utils.py	92.64% <0.00%> (+3.43%)	⬆️

---

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[Spacetown]

Differences in coverage are because the report is know generated under ubuntu.

[latk]

Would it be possible to collect coverage in one Windows build as well? Codecov merges multiple uploaded reports, which is helpful because we have some Windows- and some Linux-specific tests.

I'll delete Appveyor ass soon as you say so, or when this PR is merged.

[latk]

Looks good!

I think the Appveyor config can be deleted as well.

[Spacetown]

@latk It seems that with the GitHub actions the data is visible as comment but the test is missing. I'll try to call the commen codecov -X gcov search used in appveyor to upload the data. Codecov.io support user defined flags for the upload, I'll try to flag with the OS.

[Spacetown]

@latk The requred appveyor test can be removed.

[latk]

ok done, Appveyor is deleted. Thank you very much for making this possible!

[Spacetown]

And what about the missing needed test? Was there a special configuration on appveyor?

[latk]

I think the codecov website is just unreliable in the diff view, but is actually processing the correct data. So I don't think anything has to be fixed regarding coverage collection (at least on our part).

[Spacetown]

Strange, now the codecov is listed again. ???
Maybe this was an issue with the required appveyor test.