Bump MSTest.TestAdapter from 3.7.1 to 3.7.3 (#200)

Bumps [MSTest.TestAdapter](https://github.com/microsoft/testfx) from 3.7.1 to 3.7.3.
- [Release notes](https://github.com/microsoft/testfx/releases)
- [Changelog](https://github.com/microsoft/testfx/blob/main/docs/Changelog.md)
- [Commits](microsoft/testfx@v3.7.1...v3.7.3)

---
updated-dependencies:
- dependency-name: MSTest.TestAdapter
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

Analyzers/Akade.IndexedSet.Analyzers.Test/Akade.IndexedSet.Analyzers.Test.csproj

@@ -9,7 +9,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.12.0" />
-    <PackageReference Include="MSTest.TestAdapter" Version="3.7.1" />
+    <PackageReference Include="MSTest.TestAdapter" Version="3.7.3" />
     <PackageReference Include="MSTest.TestFramework" Version="3.7.3" />
     <PackageReference Include="Microsoft.CodeAnalysis" Version="4.12.0" />
     <PackageReference Include="Microsoft.CodeAnalysis.CSharp.Analyzer.Testing" Version="1.1.2" />

SourceGenerator/Akade.IndexedSet.InternalSourceGenerator.Tests/Akade.IndexedSet.InternalSourceGenerator.Tests.csproj

@@ -9,7 +9,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.12.0" />
-    <PackageReference Include="MSTest.TestAdapter" Version="3.7.1" />
+    <PackageReference Include="MSTest.TestAdapter" Version="3.7.3" />
     <PackageReference Include="MSTest.TestFramework" Version="3.7.3" />
     <PackageReference Include="coverlet.collector" Version="6.0.4">
       <PrivateAssets>all</PrivateAssets>