Add unit test for ToolStripInSituService

[John-Qiao]

Related #10773

Proposed changes

• Add unit test ToolStripInSituServiceTests.cs for properties and methods of the ToolStripInSituService.

Microsoft Reviewers: Open in CodeFlow

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 76.11337%. Comparing base (8ef1b9c) to head (c07d104).
Report is 82 commits behind head on main.

Additional details and impacted files

@@                 Coverage Diff                 @@
##                main      #13021         +/-   ##
===================================================
+ Coverage   75.97321%   76.11337%   +0.14016%     
===================================================
  Files           3265        3276         +11     
  Lines         643286      643879        +593     
  Branches       47431       47460         +29     
===================================================
+ Hits          488725      490078       +1353     
+ Misses        150991      150230        -761     
- Partials        3570        3571          +1     

Flag	Coverage Δ
Debug	76.11337% <100.00000%> (+0.14016%)	⬆️
integration	18.04023% <ø> (+0.02806%)	⬆️
production	50.14895% <ø> (+0.28327%)	⬆️
test	96.95079% <100.00000%> (-0.00241%)	⬇️
unit	47.58260% <ø> (+0.25759%)	⬆️

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