Update remote commitment number on CommitmentSigned (not RevokeAndAck)

Commitment numbers of each parties are independent. Updating remote
commitment number after received RevokeAndAck effectively means we are
using the same commitment number.

src/ckb/channel.rs

@@ -2852,6 +2852,7 @@ impl ChannelActorState {
                 }
             }
         }
+        self.increment_remote_commitment_number();
         Ok(())
     }
 
@@ -2969,7 +2970,6 @@ impl ChannelActorState {
             self.get_current_commitment_number(false) + 1
         );
         self.remote_commitment_points.push(commitment_point);
-        self.increment_remote_commitment_number();
     }
 
     pub fn handle_revoke_and_ack_message(