Remove unknown ItemGroup tag from csproj

test/Discord.Net.Tests/Discord.Net.Tests.csproj

@@ -27,7 +27,4 @@
     <PackageReference Include="xunit.runner.visualstudio" Version="2.2.0" />
     <PackageReference Include="xunit.runner.reporters" Version="2.2.0" />
   </ItemGroup>
-  <ItemGroup>
-    <Service Include="{82a7f48d-3b50-4b1e-b82e-3ada8210c358}" />
-  </ItemGroup>
 </Project>