Bump Microsoft.NET.Test.Sdk from 16.8.0 to 16.8.3 in /src (#101)

Bumps [Microsoft.NET.Test.Sdk](https://github.com/microsoft/vstest) from 16.8.0 to 16.8.3.
- [Release notes](https://github.com/microsoft/vstest/releases)
- [Commits](microsoft/vstest@v16.8.0...v16.8.3)

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

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

src/BBT.MaybePattern.Tests/BBT.MaybePattern.Tests.csproj

@@ -20,7 +20,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.8.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.8.3" />
     <PackageReference Include="Shouldly" Version="4.0.1" />
     <PackageReference Include="xunit" Version="2.4.1" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.4.3">