* Refactor the various email/phone management UI into a single component
These were basically the same component copied & pasted 3 times and
tweaked to match the behaviour of each case. This de-dupes them into
one component.
This all could really benefit from playwright tests, but would require
setting up a dummy ID server in the playwright tests. This is all legacy
pre-MAS stuff so its questionable whether its worth the effort.
* Basic test, remove old tests
* Use different text to confirm remove & put headers back
although the two texts are both 'Remove' in practice
* Remove string
This was never triggered anyway with sydent & synapse because they
don't seem to agree on what error to return. In any case, I think it
makes more sense for it to be consistent with the email path, ie. using
a dialog.
* Avoid nested forms
* Snapshots
* More snapshots
* Test the hs side
* Snapshots
* Test IS bind/revoke
* Test remove can be cancelled
* Test unvalidated cases & fix phone error
* Reset state between tests
* Import useState directly
* One more direct React import
