Bump dotnet-stryker to 4.8.1

[martincostello]

Update dotnet-stryker to 4.8.1.

[Copilot]

Pull Request Overview

Updates the dotnet-stryker mutation testing tool from version 4.7.0 to 4.8.1 in the .NET tools configuration.

• Bump dotnet-stryker version from 4.7.0 to 4.8.1

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.12%. Comparing base (de3cb78) to head (603c541).
⚠️ Report is 3 commits behind head on main.
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2739   +/-   ##
=======================================
  Coverage   96.12%   96.12%           
=======================================
  Files         309      309           
  Lines        7118     7118           
  Branches     1008     1008           
=======================================
  Hits         6842     6842           
  Misses        222      222           
  Partials       54       54           

Flag	Coverage Δ
linux	96.12% <ø> (ø)
macos	96.12% <ø> (ø)
windows	96.11% <ø> (ø)

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