warnAsError in CI

[yufeih]

So warnings break CI.

Related #7071 dotnet/roslyn#43051

Microsoft Reviewers: Open in CodeFlow

[codecov]

Codecov Report

Merging #7123 (8a30804) into v3 (fe66886) will decrease coverage by 0.03%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##               v3    #7123      +/-   ##
==========================================
- Coverage   84.11%   84.08%   -0.04%     
==========================================
  Files         373      373              
  Lines       14534    14534              
  Branches     2764     2764              
==========================================
- Hits        12226    12221       -5     
- Misses       1737     1742       +5     
  Partials      571      571              

Impacted Files	Coverage Δ
src/docfx/lib/git/GitUtility.cs	55.85% <0.00%> (-4.51%)	⬇️

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[ghost]

Apologies, I am afraid I am encountering technical difficulties that might have hampered my ability to assist with merging this pull request. I will continue to try to assist if there are further changes to this pull request.