scheduler: fix flaky test TestRegionLabelDenyScheduler (tikv#8340)

close tikv#8339

Ignore the specified operator instead of skipping all operators

Signed-off-by: okJiang <819421878@qq.com>

Co-authored-by: Hu# <jinhao.hu@pingcap.com>

pkg/schedule/schedulers/scheduler_controller.go

@@ -478,8 +478,8 @@ retry:
 
 		// If we have schedule, reset interval to the minimal interval.
 		s.nextInterval = s.Scheduler.GetMinInterval()
-		for _, op := range ops {
-			region := s.cluster.GetRegion(op.RegionID())
+		for i := 0; i < len(ops); i++ {
+			region := s.cluster.GetRegion(ops[i].RegionID())
 			if region == nil {
 				continue retry
 			}
@@ -492,9 +492,13 @@ retry:
 			// Refer: https://docs.pingcap.com/tidb-in-kubernetes/stable/restart-a-tidb-cluster#perform-a-graceful-restart-to-a-single-tikv-pod
 			if labelMgr.ScheduleDisabled(region) && !isEvictLeaderScheduler {
 				denySchedulersByLabelerCounter.Inc()
-				continue retry
+				ops = append(ops[:i], ops[i+1:]...)
+				i--
 			}
 		}
+		if len(ops) == 0 {
+			continue
+		}
 		return ops
 	}
 	s.nextInterval = s.Scheduler.GetNextInterval(s.nextInterval)