Unable to compile NET Core project with localized stream resources

_From @amrmahdi on May 10, 2018 0:38_

* Platform: Windows
* TargetFramework: netcore2.0
* dotnet version: 2.1.300-preview2-008533

I'm not able to get a vanilla NET Core app to with localized stream resources to compile. The app is targeting net core 2.0. I've created a repo with a simple project to repro the error: https://github.com/amrmahdi/dotnetcore-localized-resources

The error that I get is
```
E:\repro\Resources\AudioFiles.en-US.resx(123,5): error MSB3103: Invalid Resx file. Could not load file or assembly 'System.Runtime.Extensions, Version=4.2.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencie s. Reference assemblies should not be loaded for execution. They can only be loaded in the Reflection-only loader context. (Exception from HRESULT: 0x80131058) Line 123, position 5. [E:\repro\repro.csproj]
E:\repro\Resources\AudioFiles.es-ES.resx(123,5): error MSB3103: Invalid Resx file. Could not load file or assembly 'file:///C:\Program Files\dotnet\sdk\NuGetFallbackFolder\microsoft.netcore.app\2.0.0\ref\netcoreapp2.0\System.Runtime.Ex tensions.dll' or one of its dependencies. Reference assemblies should not be loaded for execution. They can only be loaded in the Reflection-only loader context. (Exception from HRESULT: 0x80131058) Line 123, position 5. [E:\repro\repro .csproj]
```

The resource files are added using the Visual studio experience.

_Copied from original issue: dotnet/sdk#2228_