RoomDataSource: Fix bubble cell data additional content height update.
RoomDataSource: Fix bubble cell data additional content height update.

vector-im/vector-ios,vector-im/riot-ios,vector-im/vector-ios,vector-im/riot-ios,vector-im/riot-ios,vector-im/riot-ios,vector-im/vector-ios,vector-im/riot-ios,vector-im/riot-ios