Bump Microsoft.NET.Test.Sdk from 17.7.2 to 17.8.0 (#74)

Bumps [Microsoft.NET.Test.Sdk](https://github.com/microsoft/vstest) from 17.7.2 to 17.8.0.
- [Release notes](https://github.com/microsoft/vstest/releases)
- [Changelog](https://github.com/microsoft/vstest/blob/main/docs/releases.md)
- [Commits](microsoft/vstest@v17.7.2...v17.8.0)

---
updated-dependencies:
- dependency-name: Microsoft.NET.Test.Sdk
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

src/Directory.Build.props

@@ -18,7 +18,7 @@
     <TestsNetCore>netcoreapp3.1</TestsNetCore>
     <XunitVersion>2.5.1</XunitVersion>
     <XunitRunnerVisualstudio>2.5.1</XunitRunnerVisualstudio>
-    <TestSdkVersion>17.7.2</TestSdkVersion>
+    <TestSdkVersion>17.8.0</TestSdkVersion>
 
     <AkkaVersion>1.5.13</AkkaVersion>
     <AkkaHostingVersion>1.5.13</AkkaHostingVersion>