Add csharp docfx (#12596)
* add docfx and gh action to build docs
* kick off build from feature branch
* Fix LGTM linting
* update az pipeline to win22 & remove nuget install
* remove azure ci changes
* fix implicit using to support 5.0
* fix more js issues
* remove resource designer changes
* remove space
* fix linting misspellings in autogenerated js temp
* fix misspellings in generated code
* delete log file
