[CI] Add coveragepy and remove ignore: test

[christophfroehlich]

Recently we worked a lot on the spawner scripts, maybe we should add coverage data also for them.

The only problem is that we don't test them with pytest but with system calls from C++ files. This needs to manually invoke coverage.py with the python modules by the std::system calls instead of using ros2 run

Most of the necessary changes are ros-controls/ros2_control_ci#115

Recently, the codecov setting to ignore the test folders did not work and they got included (which increased our coverage numbers). I removed the ignore line, and intentional add the tests to the coverage where there are good arguments for it anyways.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 86.73%. Comparing base (07fb4f3) to head (7fa5b1f).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1668      +/-   ##
==========================================
+ Coverage   84.59%   86.73%   +2.13%     
==========================================
  Files         115      115              
  Lines       10537    10539       +2     
  Branches      972      972              
==========================================
+ Hits         8914     9141     +227     
+ Misses       1295     1052     -243     
- Partials      328      346      +18     

Flag	Coverage Δ
unittests	86.73% <100.00%> (+2.13%)	⬆️

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

Files	Coverage Δ
controller_manager/test/test_spawner_unspawner.cpp	99.00% <100.00%> (+0.01%)	⬆️

... and 5 files with indirect coverage changes

[mergify]

This pull request is in conflict. Could you fix it @christophfroehlich?

[bmagyar]

alles gut

[saikishor]

LGTM