We have existing logic to attempt to reliably send a channel update to
the remote peer. In the wild, we've seen this fail, as it's possible
right when we send the update the peer disconnects.
In this commit, we implement a simple fix which is just to send the chan
update each time we connect to the remote party.
Fixes https://github.com/lightningnetwork/lnd/issues/6870.
Olaoluwa Osuntokun
9acad37f57