Fix metric label for phase from uppercase to titlecase (#4685)

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#### What type of PR is this?

Fix

#### What this PR does / why we need it

Have a same label value across metrics

---------

Signed-off-by: Nikola Jokic <jokicnikola07@gmail.com>
Co-authored-by: John Popplewell <john.popplewell@gresearch.co.uk>
Co-authored-by: Maurice Yap <mauriceyap@hotmail.co.uk>
Co-authored-by: Dejan Zele Pejchev <pejcev.dejan@gmail.com>

Author: 4 people

internal/scheduler/metrics.go

@@ -443,7 +443,7 @@ func (c *MetricsCollector) updateClusterMetrics(ctx *armadacontext.Context) ([]p
 						nodeJobsMetricCounts[nodeJobPhaseMetricKey{
 							node:    node.Name,
 							cluster: executor.Id,
-							phase:   phase,
+							phase:   strings.Title(strings.ToLower(phase)),
 						}]++
 					}
 

internal/scheduler/metrics_test.go

@@ -348,8 +348,8 @@ func TestMetricsCollector_TestCollect_ClusterMetrics(t *testing.T) {
 				commonmetrics.NewPoolInfoMetric(testfixtures.TestPool),
 				commonmetrics.NewQueueLeasedPodCount(1, "cluster-1", testfixtures.TestPool, testfixtures.TestQueue, "Pending", "type-1", "none"),
 				commonmetrics.NewQueueLeasedPodCount(1, "cluster-1", testfixtures.TestPool, testfixtures.TestQueue, "Running", "type-1", "none"),
-				commonmetrics.NewNodeJobPhaseCountMetric(1, nodeWithJobs.Name, "cluster-1", "PENDING"),
-				commonmetrics.NewNodeJobPhaseCountMetric(1, nodeWithJobs.Name, "cluster-1", "RUNNING"),
+				commonmetrics.NewNodeJobPhaseCountMetric(1, nodeWithJobs.Name, "cluster-1", "Pending"),
+				commonmetrics.NewNodeJobPhaseCountMetric(1, nodeWithJobs.Name, "cluster-1", "Running"),
 				commonmetrics.NewQueueAllocated(2, testfixtures.TestQueue, "cluster-1", testfixtures.TestPool, testfixtures.TestDefaultPriorityClass, "None", "cpu", "type-1", "none"),
 				commonmetrics.NewQueueAllocated(2*1024*1024*1024, testfixtures.TestQueue, "cluster-1", testfixtures.TestPool, testfixtures.TestDefaultPriorityClass, "None", "memory", "type-1", "none"),
 				commonmetrics.NewQueueUsed(1, testfixtures.TestQueue, "cluster-1", testfixtures.TestPool, "cpu", "type-1", "none"),