Bump Microsoft.NET.Test.Sdk from 16.7.1 to 16.8.0 (#121)

Bumps [Microsoft.NET.Test.Sdk](https://github.com/microsoft/vstest) from 16.7.1 to 16.8.0.
- [Release notes](https://github.com/microsoft/vstest/releases)
- [Commits](microsoft/vstest@v16.7.1...v16.8.0)

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

Co-authored-by: dependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

Author: dependabot-preview[bot]

src/common.props

@@ -12,7 +12,7 @@
   </PropertyGroup>
   <PropertyGroup>
     <XunitVersion>2.4.1</XunitVersion>
-    <TestSdkVersion>16.7.1</TestSdkVersion>
+    <TestSdkVersion>16.8.0</TestSdkVersion>
     <NBenchVersion>2.0.1</NBenchVersion>
     <AkkaVersion>1.4.11</AkkaVersion>
     <NetCoreTestVersion>netcoreapp3.1</NetCoreTestVersion>