[PORT] Add new fields and remove auto-generated text.

[tomlm]

Port this change from botbuilder-dotnet/master branch:
microsoft/botbuilder-dotnet#3499

fixes: #3497

Changes:

• Add ChannelCount and MemberCount to TeamDetails object
• Remove auto-generated documentation
• Move file out of the generated folder to make clear this is no longer auto-generated

Changed projects

• Microsoft.Bot.Schema

[parity with python]

[clearab]

Closing as duplicate.