Bump MSTest.TestAdapter from 3.6.3 to 3.6.4 in /updater

Bumps [MSTest.TestAdapter](https://github.com/microsoft/testfx) from 3.6.3 to 3.6.4.
- [Release notes](https://github.com/microsoft/testfx/releases)
- [Changelog](https://github.com/microsoft/testfx/blob/main/docs/Changelog.md)
- [Commits](microsoft/testfx@v3.6.3...v3.6.4)

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

Signed-off-by: dependabot[bot] <[email protected]>

updater-test/updater-test.csproj

@@ -15,7 +15,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.12.0" />
-    <PackageReference Include="MSTest.TestAdapter" Version="3.6.3" />
+    <PackageReference Include="MSTest.TestAdapter" Version="3.6.4" />
     <PackageReference Include="MSTest.TestFramework" Version="3.6.3" />
     <PackageReference Include="coverlet.collector" Version="6.0.2">
       <PrivateAssets>all</PrivateAssets>