System information

• OS version/distro: Windows 7
• .NET Version (eg., dotnet --info): core 3.1

Issue

When trying to use OnnxTransformer, the native libraries aren't loaded properly. I can see them under bin\Debug\netcoreapp3.1\runtimes(platform)\native.
If I use package version 1.4.0 of OnnxTransformer, without installing the runtime myself, it works.
I couldn't find any docs regarding the requirement to install the runtime manually (I figured it out by browsing all over the place, but not through docs really). I suppose this should be clear when you're not using the onnxruntime package explicitly, but rather the higher level API of OnnxTransformer?

On a separate note: Is it sufficient to install the GPU natives and use the fallbackToCpu flag of ApplyOnnxModel to be able to run inferencing on both CPU and GPU? I'm having a hard time finding this documented.

• What did you do?
  Installed Microsoft.ML.OnnxTransformer 1.5.0 and Microsoft.ML.OnnxRuntime 1.3.0 and used ApplyOnnxModel in a pipeline.

• What happened?
  Calling ApplyOnnxModel throws System.TypeInitializationException.

• What did you expect?
  That my ONNX model can be used.

Source code / logs

Inner exception message:

"Unable to load DLL 'onnxruntime' or one of its dependencies: The specified module could not be found. (0x8007007E)"