multi: Fix typos [skip ci]

channeldb/migration21/current/current_encoding.go

@@ -280,7 +280,7 @@ func SerializeChannelCloseSummary(w io.Writer, cs *common.ChannelCloseSummary) e
 
 	// The RemoteNextRevocation field is optional, as it's possible for a
 	// channel to be closed before we learn of the next unrevoked
-	// revocation point for the remote party. Write a boolen indicating
+	// revocation point for the remote party. Write a boolean indicating
 	// whether this field is present or not.
 	if err := WriteElements(w, cs.RemoteNextRevocation != nil); err != nil {
 		return err