Please support MSC4171

### Your use case

#### What would you like to do?
I'm using mautrix-signal bridge, and private chatrooms are named by the signal-user AND the bridge-bot-user.
I discussed this in the chatroom for mautrix-signal bridge and realizied, that element X does not support MSC4171.

In legacy Element the rooms are named only after the Signal-user. That's what i expect.

#### Why would you like to do it?
Consistent room namings in bridged rooms.

#### How would you like to achieve it?
--

### Have you considered any alternatives?

Think it is only necessary, that element x has to implement MSC4171

### Additional context

Element X V0.6.3

### Are you willing to provide a PR?

No

No file, test, or entry point is named. Start by reading MSC4171 and reproducing the private bridged-room naming case described for mautrix-signal; done means Element X names the room after the Signal user without including the bridge-bot user.

Written by the indexing model from the issue text.