Copying files to transport feeds not working for 7.0 in release pipline

[michellemcdaniel]

The release pipeline makes an assumption about what channels are allowed for copying transport packages that does not consider new version of .NET (it just handles 6.0, 5.0, and 3.1). Code for making a decision on if we are copying transport packages is here: https://dev.azure.com/dnceng/internal/_git/dotnet-release?path=/eng/pipeline/tools/write-transport-nuget.ps1&version=GBmain&line=22&lineEnd=39&lineStartColumn=1&lineEndColumn=1&lineStyle=plain&_a=contents

We need this to be somehow parameterizable so that going forward with future releases, we do not have to update the code.

This is currently blocking some aspects of the .NET 7 releases.