[telemetry] Fix scheduler queue count telemetry metric (#6247)

It was tagged by check_name, which doesn't make sense since it's
incremented when a new scheduler queue is created, so it should
count the total number of queues.

If we want to track the check names per queue, we should introduce
another telemetry metric (I'm not sure if it's worth counting that
though).

pkg/aggregator/aggregator.go

@@ -105,7 +105,7 @@ var (
 	aggregatorHostnameUpdate                   = expvar.Int{}
 
 	tlmFlush = telemetry.NewCounter("aggregator", "flush",
-		[]string{"data_type", "state"}, "Count of flush")
+		[]string{"data_type", "state"}, "Number of metrics/service checks/events flushed")
 	tlmProcessed = telemetry.NewCounter("aggregator", "processed",
 		[]string{"data_type"}, "Amount of metrics/services_checks/events processed by the aggregator")
 	tlmHostnameUpdate = telemetry.NewCounter("aggregator", "hostname_update",

pkg/collector/scheduler/scheduler.go

@@ -27,7 +27,7 @@ var (
 	tlmChecksEntered = telemetry.NewGauge("scheduler", "checks_entered",
 		[]string{"check_name"}, "How many checks are currently tracked by the scheduler")
 	tlmQueuesCount = telemetry.NewCounter("scheduler", "queues_count",
-		[]string{"check_name"}, "How many queues were opened")
+		nil, "How many queues were opened")
 )
 
 func init() {
@@ -92,7 +92,7 @@ func (s *Scheduler) Enter(check check.Check) error {
 		s.jobQueues[check.Interval()] = newJobQueue(check.Interval())
 		s.startQueue(s.jobQueues[check.Interval()])
 		if check.IsTelemetryEnabled() {
-			tlmQueuesCount.Inc(check.String())
+			tlmQueuesCount.Inc()
 		}
 		schedulerQueuesCount.Add(1)
 	}