Remove docs for new invite dialog labs feature
Remove docs for new invite dialog labs feature

It's the default now: https://github.com/matrix-org/matrix-react-sdk/pull/3906
vector-im/riot-web,vector-im/vector-web,vector-im/riot-web,vector-im/riot-web,vector-im/vector-web,vector-im/riot-web,vector-im/vector-web,vector-im/riot-web,vector-im/vector-web,vector-im/vector-web,vector-im/riot-web