FIX: Exclude PMs that user sent to themselves. (PR #14496)

Regression from 016efeadf6f242e04daf5ef8e18c2ca708a1392d

Follow-up to 016efeadf6f242e04daf5ef8e18c2ca708a1392d


This pull request has been mentioned on Discourse Meta. There might be relevant details there:

Sometimes you want to send yourself encrypted message as a reminder, do we want to skip this?

Not sure about the use case but apparently we should exclude messages that you send to yourself in the list. This is something that didn’t make sense to me so I removed in the the associated commit but users complained on meta so I’m adding it back ehre.