Add tests for MaskedTextBoxTextEditor

[LeafShi1]

Related #10773

Proposed changes

• Add unit test MaskedTextBoxTextEditorTests.cs for public properties and method of the MaskedTextBoxTextEditor

Microsoft Reviewers: Open in CodeFlow

[codecov]

Codecov Report

Attention: Patch coverage is 99.23077% with 1 line in your changes missing coverage. Please review.

Project coverage is 74.75712%. Comparing base (c0318e5) to head (f7cf2be).
Report is 9 commits behind head on feature/10.0.

Additional details and impacted files

@@                  Coverage Diff                   @@
##           feature/10.0      #11737         +/-   ##
======================================================
+ Coverage      74.73622%   74.75712%   +0.02089%     
======================================================
  Files              3045        3046          +1     
  Lines            630638      630768        +130     
  Branches          46862       46867          +5     
======================================================
+ Hits             471315      471544        +229     
+ Misses           155957      155863         -94     
+ Partials           3366        3361          -5     

Flag	Coverage Δ
Debug	74.75712% <99.23077%> (+0.02089%)	⬆️
integration	17.96079% <ø> (+0.01652%)	⬆️
production	47.79302% <ø> (+0.03508%)	⬆️
test	96.98618% <99.23077%> (+0.00084%)	⬆️
unit	44.83540% <ø> (+0.03052%)	⬆️

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[Tanya-Solyanik]

Thank you!