Disable 'Start New Chat' button in MemberInfo if we already have chats
Disable 'Start New Chat' button in MemberInfo if we already have chats

Part of https://github.com/vector-im/riot-web/issues/10416
matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk