Add test project for c# 14

[bjornhellander]

No description provided.

[codecov]

Codecov Report

❌ Patch coverage is 96.00000% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 97.40%. Comparing base (b72b3f7) to head (ccb81f4).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #4040      +/-   ##
==========================================
+ Coverage   97.14%   97.40%   +0.26%     
==========================================
  Files         957      959       +2     
  Lines      112852   112875      +23     
  Branches     3389     3390       +1     
==========================================
+ Hits       109629   109951     +322     
+ Misses       2224     1934     -290     
+ Partials      999      990       -9     

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[sharwell]

This one's going to take me a bit. I'm planning to complete the feature audit in order and I just finished C# 8 yesterday.

[bjornhellander]

This one's going to take me a bit. I'm planning to complete the feature audit in order and I just finished C# 8 yesterday.

Not a problem. Let me know if you'd like any help.

[sharwell]

Reviews on the PRs submitted for the sub-issues of #4041 would be helpful 😄 I'm moving through these fairly quickly.

[EdwinEngelen]

I performed a (partial) review:

• All test files that exist in StyleCop.Analyzers.Test.CSharp13 also exist in StyleCop.Analyzers.Test.CSharp14
• All tests are empty / don't contain any tests
• All tests are in the CSharp14 namespace and derive from CSharp14-tests
• Tests use C# 14 (Microsoft.CodeAnalysis.CSharp.Workspaces 5.0)