XUnit tests only works in command line not VSCode GUI

I have a project that was created in VisualStudio and after migrated to Visual Studio Code. Now I have the following problem, when executing Debug Test or Run Test in VSCode:

I got the following error:

Test run will use DLL(s) built for framework .NETCoreApp,Version=v2.1 and platform X86. Following DLL(s) do not match framework/platform settings.
CoreTests.dll is built for Framework 2.0 and Platform AnyCPU.
Go to http://go.microsoft.com/fwlink/?LinkID=236877&clcid=0x409 for more details on managing these settings.

Microsoft.VisualStudio.TestPlatform.ObjectModel.TestPlatformException: Unable to find /home/ronaldo.lanhellas/Workspace/safepark/backend-netcore/CoreTests/bin/Debug/netstandard2.0/testhost.dll. Please publish your test project and retry.
   at Microsoft.VisualStudio.TestPlatform.CrossPlatEngine.Hosting.DotnetTestHostManager.GetTestHostPath(String runtimeConfigDevPath, String depsFilePath, String sourceDirectory)
   at Microsoft.VisualStudio.TestPlatform.CrossPlatEngine.Hosting.DotnetTestHostManager.GetTestHostProcessStartInfo(IEnumerable`1 sources, IDictionary`2 environmentVariables, TestRunnerConnectionInfo connectionInfo)
   at Microsoft.VisualStudio.TestPlatform.CrossPlatEngine.Client.ProxyOperationManager.SetupChannel(IEnumerable`1 sources)
   at Microsoft.VisualStudio.TestPlatform.CrossPlatEngine.Client.ProxyDiscoveryManager.DiscoverTests(DiscoveryCriteria discoveryCriteria, ITestDiscoveryEventsHandler2 eventHandler)
Debugging complete.

But executing under dotnet test command, everything works fine:

This is my CoreTests.csproj file:

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <TargetFramework>netcoreapp2.1</TargetFramework>

    <IsPackable>false</IsPackable>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="NSubstitute" Version="4.2.1" />
    <PackageReference Include="xunit" Version="2.4.1" />
    <PackageReference Include="xunit.runner.visualstudio" Version="2.4.1">
      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
      <PrivateAssets>all</PrivateAssets>
    </PackageReference>
  </ItemGroup>

  <ItemGroup>
    <ProjectReference Include="..\Core\Core.csproj" />
  </ItemGroup>

</Project>