Prior to this commit, only admins of a community could open up the community
profile popup from inside the community. However, normal members should be able
to do so too.
This was hardcoded into `isAdmin` for some reason. It also seems that the
property isn't actually used anywhere in the profile popup, so we might
as well get rid off it.
The `communityProfilePopup` relies on the currently `activeCommunity` to
get its data. Unfortunately, once read, even when `chatsModel.setActiveCommunity()`
is called which triggers `activeCommunityChanged`, the data in the popup
won't be updated. The next time one would open a community profile page,
it'd have the data that was previously received from the model.
This commit ensures that the popup is hydrated with the most recent data
by explicitly updating its properties right before it's opened.