Update: (#46444)

- MSTest.TestAdapter to 3.9.1
- MSTest.TestFramework to 3.9.1

---
updated-dependencies:
- dependency-name: MSTest.TestAdapter
  dependency-version: 3.9.1
  dependency-type: direct:production
  update-type: version-update:semver-patch
- dependency-name: MSTest.TestFramework
  dependency-version: 3.9.1
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

docs/core/testing/snippets/unit-testing-using-mstest/csharp/PrimeService.Tests/PrimeService.Tests.csproj

@@ -8,8 +8,8 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.14.0" />
-    <PackageReference Include="MSTest.TestAdapter" Version="3.9.0" />
-    <PackageReference Include="MSTest.TestFramework" Version="3.9.0" />
+    <PackageReference Include="MSTest.TestAdapter" Version="3.9.1" />
+    <PackageReference Include="MSTest.TestFramework" Version="3.9.1" />
     <PackageReference Include="coverlet.collector" Version="6.0.4">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>