Backport PR #2088 on branch 0.12.x (ci: Check PRs for semantic labels)

[flying-sheep]

Backports #2088

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 87.58%. Comparing base (96bef14) to head (a7705f5).
⚠️ Report is 1 commits behind head on 0.12.x.
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@            Coverage Diff             @@
##           0.12.x    #2091      +/-   ##
==========================================
+ Coverage   86.79%   87.58%   +0.79%     
==========================================
  Files          46       46              
  Lines        7064     7064              
==========================================
+ Hits         6131     6187      +56     
+ Misses        933      877      -56     

see 4 files with indirect coverage changes