This fixes a common React warning we see. Most of these components should be using constructors instead, however componentDidMount is just as good (and doesn't require converting most of these).
Conversion to classes will be done in a later stage of React warning fixes.
For https://github.com/vector-im/riot-web/issues/12877
Rooms which are already upgraded shouldn't be asked to upgrade. Additionally, this fixes a bug where the room upgrade dialog would stay open even after upgrading the room.
This lessens the warning for unstable-but-not-official versions while still communicating that the version is unstable. In the future, we may want to make this state dismissable.
Michael Telatynski