Make channel monitor sync in progress a trace log

This log is super spammy for us, think this makes more sense as a trace
log.

Author: benthecarman

lightning/src/chain/chainmonitor.rs

@@ -818,7 +818,7 @@ where C::Target: chain::Filter,
 					monitor_state.last_chain_persist_height.load(Ordering::Acquire) + LATENCY_GRACE_PERIOD_BLOCKS as usize
 						> self.highest_chain_height.load(Ordering::Acquire)
 			{
-				log_debug!(self.logger, "A Channel Monitor sync is still in progress, refusing to provide monitor events!");
+				log_trace!(self.logger, "A Channel Monitor sync is still in progress, refusing to provide monitor events!");
 			} else {
 				if is_pending_monitor_update {
 					log_error!(self.logger, "A ChannelMonitor sync took longer than {} blocks to complete.", LATENCY_GRACE_PERIOD_BLOCKS);