fix: correct E2E assertions and use enforced disk size for WAL tuning

- Fix PodMonitor/PrometheusRule E2E assertions: CNPG uses the CR's own
  namespace (not pg-<team>) and names are prefixed with pg-
- Use enforceMinimum2GiDisk() for WAL sizing to align with actual PVC size

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: Starefossen

internal/controller/resourcecreator/cnpg.go

@@ -238,7 +238,7 @@ func MinimalCNPGPooler(postgres *data_nais_io_v1.Postgres, clusterName, namespac
 
 func makeCNPGPostgresParameters(cluster data_nais_io_v1.PostgresCluster) map[string]string {
 	memBytes := cluster.Resources.Memory.Value()
-	diskBytes := cluster.Resources.DiskSize.Value()
+	diskBytes := enforceMinimum2GiDisk(cluster.Resources.DiskSize).Value()
 
 	// PostgreSQL memory tuning parameters based on available memory
 	sharedBuffers := memBytes / sharedBuffersFraction

tests/e2e/postgres-cnpg-basic/chainsaw-test.yaml

@@ -83,8 +83,8 @@ spec:
               apiVersion: monitoring.coreos.com/v1
               kind: PodMonitor
               metadata:
-                name: mydb
-                namespace: pg-cnpg-team
+                name: pg-mydb
+                namespace: cnpg-team
                 labels:
                   prometheus: tenant
               spec:
@@ -100,8 +100,8 @@ spec:
               apiVersion: monitoring.coreos.com/v1
               kind: PrometheusRule
               metadata:
-                name: mydb
-                namespace: pg-cnpg-team
+                name: pg-mydb
+                namespace: cnpg-team
     - name: Assert engine annotation set
       try:
         - assert: