Bump Microsoft.NET.Test.Sdk from 15.9.0 to 16.9.4 (#152)

Bumps [Microsoft.NET.Test.Sdk](https://github.com/microsoft/vstest) from 15.9.0 to 16.9.4.
- [Release notes](https://github.com/microsoft/vstest/releases)
- [Commits](microsoft/vstest@v15.9.0...v16.9.4)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

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

src/common.props

@@ -16,6 +16,6 @@ Updated Quartz to 3.0.7</PackageReleaseNotes>
     <AkkaVersion>1.4.18</AkkaVersion>
     <QuartzVersion>3.3.2</QuartzVersion>
     <XunitVersion>2.4.1</XunitVersion>
-    <TestSdkVersion>15.9.0</TestSdkVersion>
+    <TestSdkVersion>16.9.4</TestSdkVersion>
   </PropertyGroup>
 </Project>