[build] Migrate SonarCloud to GitHub Action (PR within the repo).

[maxsharabayko]

Fixes #2851.

TODO

• CodeCoverage not found.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 64.81%. Comparing base (03aa5e4) to head (5241a20).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2910      +/-   ##
==========================================
- Coverage   64.97%   64.81%   -0.17%     
==========================================
  Files         101      101              
  Lines       17525    17522       -3     
==========================================
- Hits        11387    11357      -30     
- Misses       6138     6165      +27     

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[sonarqubecloud]

Quality Gate failed

Failed conditions
3 Security Hotspots
43.3% Coverage on New Code (required ≥ 80%)
D Maintainability Rating on New Code (required ≥ A)
E Reliability Rating on New Code (required ≥ A)

See analysis details on SonarCloud

Catch issues before they fail your Quality Gate with our IDE extension SonarLint

[ethouris]

I think there are some needed improvements:

1. The code from the libsrtsupport and all testing applications should be excluded from checking.
2. The C++ standard should be correctly applied to particular parts

I think the best would be if the checks focus exclusively on srtcore, haicrypt and common directories and defines C++03 as the C++ standard for all checks.

[maxsharabayko]

I think there are some needed improvements:

1. The code from the libsrtsupport and all testing applications should be excluded from checking.
2. The C++ standard should be correctly applied to particular parts

I think the best would be if the checks focus exclusively on srtcore, haicrypt and common directories and defines C++03 as the C++ standard for all checks.

The 1st should be done via Quality Profiles. Would be nice to apply C++03 on the core, but C++11 on apps.
Another topic is that Sonarcloud still likely does not check PRs submitted from external repos.

[maxsharabayko]

Merging to experiment with external PRs.