Add namespace to operator through DownwardAPI

The namespace attribute is now accessible to the Operator
itself.

Issue: [sc-12903]

Author: benjaminjb

helm/install/templates/manager.yaml

@@ -19,6 +19,10 @@ spec:
       - name: operator
         image: "{{ .Values.image.repository }}/postgres-operator:{{ .Values.image.tag }}"
         env:
+        - name: PGO_NAMESPACE
+          valueFrom:
+            fieldRef:
+              fieldPath: metadata.namespace
         - name: CRUNCHY_DEBUG
           value: "true"
         {{- range  $image_name, $image_val := .Values.relatedImages }}

kustomize/install/bases/manager/manager.yaml

@@ -12,6 +12,10 @@ spec:
       - name: operator
         image: postgres-operator
         env:
+        - name: PGO_NAMESPACE
+          valueFrom:
+            fieldRef:
+              fieldPath: metadata.namespace
         - name: CRUNCHY_DEBUG
           value: "true"
         - name: RELATED_IMAGE_POSTGRES_13