fix LeaderTransitions always zero

on leader transition, LeaderTransitions is increased to 1, but
then cleared to zero by next renew.

External monitoring system may watch LeaderTransitions and rely
on it's facticity.

pkg/client/leaderelection/leaderelection.go

@@ -253,6 +253,7 @@ func (le *LeaderElector) tryAcquireOrRenew() bool {
 	// here. Let's correct it before updating.
 	if oldLeaderElectionRecord.HolderIdentity == le.config.Lock.Identity() {
 		leaderElectionRecord.AcquireTime = oldLeaderElectionRecord.AcquireTime
+		leaderElectionRecord.LeaderTransitions = oldLeaderElectionRecord.LeaderTransitions
 	} else {
 		leaderElectionRecord.LeaderTransitions = oldLeaderElectionRecord.LeaderTransitions + 1
 	}