Centralize GitHub workflows and add code coverage

[perseoGI]

Changelog: Omit
Docs: Omit

Merge workflows, recover coverage from all test results and report them.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Please upload report for BASE (develop2@6296e6f). Learn more about missing BASE report.

Additional details and impacted files

@@             Coverage Diff             @@
##             develop2   #17481   +/-   ##
===========================================
  Coverage            ?   89.36%           
===========================================
  Files               ?      247           
  Lines               ?    22035           
  Branches            ?        0           
===========================================
  Hits                ?    19692           
  Misses              ?     2343           
  Partials            ?        0           

[memsharded]

why these weird paths with /runner/?
Why the conans path is not included?

[perseoGI]

This is a tricky behavior of coverage tool. Coverage files are generated across different OS and machines, thus, coverage reports will contain different absolute paths to reference to the same project relative paths.
These absolute "regex" paths are needed by coverage to merge those reports into a single one.

The first path has to be the relative path to the project, in this case, conan. Conan is interpreted as conan main git folder, not the conan subfolder so it should be able to merge other paths such as conans and test.
Anyway, I'm running a quick test in a workflow right now to validate this last statement.

Useful links:

• https://coverage.readthedocs.io/en/coverage-4.0.3/config.html#paths
• https://coverage.readthedocs.io/en/coverage-4.0.3/cmd.html#cmd-combining

[perseoGI]

In the end we didn't need to define the path option as there exists a relative_files option which tells coverage to generate file reports relative to project path

[memsharded]

Just the issue with the weird paths. Otherwise, if it only builds for develop2 branch, assigning it to @czoido

[memsharded]

running tests on powershell on windows can affect the result of the tests, as things that conan generates, as virtualenv files, etc, won't work for powershell

[perseoGI]

Since 2019, powershell is the default shell in windows runners in GitHub.
This change just tries to emulates what we have doing in the past before moving pytest execution to a GitHub composite action.

A support example:
https://github.com/conan-io/conan/actions/runs/12906022606/job/35986463253#step:18:34
This is a recent windows functional test workflow where it can be seen that pwsh is the shell in usage by the windows job.