Fixing issue described in ENG-10144#comment-16a38c06.

Tracked in ENG-10181.

1. There is no need to create a dangling olm.Account when we're going to return notif the account was created elsewhere.
2. Freeing memory of the notif account created as part of getNotifsCryptoAccount.

This logic is messy, it is doing some weird migration I don't have much context on, so I am not doing any refactoring here to not break it.

Depends on D14352

Refresh app (this is executed on start).