Missing SDK when setting MSBUILD_EXE_PATH to .NET Core 3.0 MSBuild.dll

[bugproof]

https://blog.rsuter.com/missing-sdk-when-using-the-microsoft-build-package-in-net-core/ (this fix was working until I installed .NET Core 3 SDK)

MSBuild.dll from 3.0 SDK seems to break something and the workaround doesn't work anymore.

Steps to reproduce

<PackageReference Include="Microsoft.Build" Version="15.9.20" />
<PackageReference Include="Microsoft.Build.Framework" Version="15.9.20" />
<PackageReference Include="Microsoft.Build.Tasks.Core" Version="15.9.20" />
<PackageReference Include="Microsoft.Build.Utilities.Core" Version="15.9.20" />

using Microsoft.Build.Definition;
using Microsoft.Build.Evaluation;

// Program.Main

Environment.SetEnvironmentVariable("MSBUILD_EXE_PATH", @"C:\Program Files\dotnet\sdk\3.0.100-preview3-010431\MSBuild.dll");
//2.2.104 works
// Environment.SetEnvironmentVariable("MSBUILD_EXE_PATH", @"C:\Program Files\dotnet\sdk\2.2.104\MSBuild.dll");
// throws exception , uncomment previous line and see that it will fix it
var project = Project.FromFile("someproject.csproj", new ProjectOptions()); 

@rainersigwald

#2532

[bugproof]

It appears to be working again in the GA release. I'm not 100% sure