feat(f3): log a warning when we lose an F3 participation lease

chain/lf3/participation_lease.go

@@ -110,6 +110,7 @@ func (l *leaser) getParticipantsByInstance(instance uint64) []uint64 {
 		if instance > lease.ToInstance() {
 			// Lazily delete the expired leases.
 			delete(l.leases, id)
+			log.Warnf("lost F3 participation lease for miner f0%d", id)
 		} else {
 			participants = append(participants, id)
 		}