Use vstest Cobertura support (#1177)

* Use vstest Cobertura support

Thanks to https://github.com/microsoft/vstest/issues/2874 Cobertura reports can be obtained faster without coverlet.

* Update Kubectl.Tests.csproj

* Update KubernetesClient.Classic.Tests.csproj

* Update KubernetesClient.Tests.csproj

* Update buildtest.yaml

* Update AbstractKubernetes.cs.template

* Update IBasicKubernetes.cs.template

* Update IOperations.cs.template

* Update Model.cs.template

* Add filter

* revert

tests/Kubectl.Tests/Kubectl.Tests.csproj

@@ -9,11 +9,6 @@
   </PropertyGroup>
   <ItemGroup>
 
-    <PackageReference Include="coverlet.msbuild" Version="3.2.0">
-      <PrivateAssets>all</PrivateAssets>
-      <IncludeAssets>runtime; build; native; contentfiles; analyzers</IncludeAssets>
-    </PackageReference>
-
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.4.1" />
     <PackageReference Include="xunit" Version="2.4.2" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.4.5">
@@ -36,4 +31,4 @@
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </AdditionalFiles>
   </ItemGroup>
-</Project>
+</Project>