onnxruntime

ee5ca27a - Split Microsoft.AI.MachineLearning.nupkg in a NuGet package and symbol NuGet package (#4503)

Split Microsoft.AI.MachineLearning.nupkg in a NuGet package and symbol NuGet package (#4503) * add threadpool interface * generate snupkgs * include_pdb check * fix snupkg generation * Add task to merge snupkgs * folder exists * check dir * revert thread pool stuff Co-authored-by: Sheil Kumar <sheilk@microsoft.com>