Bump MSTest.TestFramework and Verify.MSTest (#194)

Bumps [MSTest.TestFramework](https://github.com/microsoft/testfx) and [Verify.MSTest](https://github.com/VerifyTests/Verify). These dependencies needed to be updated together.

Updates `MSTest.TestFramework` from 3.6.4 to 3.7.0
- [Release notes](https://github.com/microsoft/testfx/releases)
- [Changelog](https://github.com/microsoft/testfx/blob/main/docs/Changelog.md)
- [Commits](microsoft/testfx@v3.6.4...v3.7.0)

Updates `Verify.MSTest` from 28.4.0 to 28.8.1
- [Release notes](https://github.com/VerifyTests/Verify/releases)
- [Commits](https://github.com/VerifyTests/Verify/commits)

---
updated-dependencies:
- dependency-name: MSTest.TestFramework
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: Verify.MSTest
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

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

@@ -10,13 +10,13 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.12.0" />
     <PackageReference Include="MSTest.TestAdapter" Version="3.6.3" />
-    <PackageReference Include="MSTest.TestFramework" Version="3.6.4" />
+    <PackageReference Include="MSTest.TestFramework" Version="3.7.0" />
     <PackageReference Include="coverlet.collector" Version="6.0.2">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
     <PackageReference Include="Verify.DiffPlex" Version="3.1.2" />
-    <PackageReference Include="Verify.MSTest" Version="28.4.0" />
+    <PackageReference Include="Verify.MSTest" Version="28.8.1" />
     <PackageReference Include="Verify.SourceGenerators" Version="2.5.0" />
   </ItemGroup>