Bump MSTest from 3.7.2 to 3.7.3

Bumps [MSTest](https://github.com/microsoft/testfx) from 3.7.2 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@v3.7.2...v3.7.3)

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

Signed-off-by: dependabot[bot] <support@github.com>

Directory.Build.targets

@@ -37,7 +37,7 @@
     <Using Include="Microsoft.VisualStudio.TestTools.UnitTesting" />
     <ProjectReference Include="$(SolutionDir)\$(SolutionName)\$(SolutionName).csproj" />
     <PackageReference Include="coverlet.collector" Version="6.0.4" />
-    <PackageReference Include="MSTest" Version="3.7.2" />
+    <PackageReference Include="MSTest" Version="3.7.3" />
   </ItemGroup>
 
   <ItemGroup Condition="$(IsPrimaryProject)">