chore: Expand test coverage for CometWindowsExec

[comphead]

Which issue does this PR close?

Followup on #2696 (comment)

Rationale for this change

Expand test coverage for Windows exec.

Moved window related test to CometWindowExecSuite

What changes are included in this PR?

How are these changes tested?

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 59.33%. Comparing base (f09f8af) to head (e75ab17).
⚠️ Report is 667 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #2711      +/-   ##
============================================
+ Coverage     56.12%   59.33%   +3.21%     
- Complexity      976     1448     +472     
============================================
  Files           119      147      +28     
  Lines         11743    13814    +2071     
  Branches       2251     2370     +119     
============================================
+ Hits           6591     8197    +1606     
- Misses         4012     4391     +379     
- Partials       1140     1226      +86     

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[andygrove]

Could you put all the window tests into a new CometWindowExecSuite and add the test to CI in the exec section in:

• .github/workflows/pr_build_linux.yml
• .github/workflows/pr_build_macos.yml

[andygrove]

Thanks @comphead