Addresses #8579
I might be getting the hang of **_find and replace_** now. 😝
This doesn't touch a couple that ref 2.2.0. I'll tidy those up on https://github.com/aspnet/Docs/issues/8518 after 2.2 RTM.
* Fix SignalR .NET client sample app
* Adjust line numbers in associated doc
* Fix HintPaths
* Convert packages.config to PackageReferences
* Add launchSettings.json to ensure same port WPF app expects is used