Add initial version of flux experiments

clusters/okd4/infrastructure.yaml

+apiVersion: kustomize.toolkit.fluxcd.io/v1beta1
+kind: Kustomization
+metadata:
+  name: infrastructure
+  namespace: flux-system
+spec:
+  interval: 10m0s
+  sourceRef:
+    kind: GitRepository
+    name: flux-system
+  path: ./infrastructure
+  prune: true
+  validation: client

infrastructure/kustomization.yaml

+apiVersion: kustomize.config.k8s.io/v1beta1
+kind: Kustomization
+resources:
+  - sources
+  - postgres

infrastructure/postgres/kustomization.yaml

+apiVersion: kustomize.config.k8s.io/v1beta1
+kind: Kustomization
+namespace: zalando-postgres
+resources:
+  - namespace.yaml
+  - release.yaml

infrastructure/postgres/namespace.yaml

+apiVersion: v1
+kind: Namespace
+metadata:
+  name: zalando-postgres

infrastructure/postgres/release.yaml

+iapiVersion: helm.toolkit.fluxcd.io/v2beta1
+kind: HelmRelease
+metadata:
+  name: zalando-postgres-operator
+  namespace: zalando-postgres
+spec:
+  releaseName: zalando-postgres-operator
+  chart:
+    spec:
+      chart: postgres-operator
+      sourceRef:
+        kind: HelmRepository
+        name: zalando-postgres-operator
+        namespace: flux-system
+      valuesFiles:
+        - values.yaml
+  interval: 5m
+  install:
+    remediation:
+      retries: 3
+  values:
+    configGeneral:
+      kubernetes_use_configmaps: true
+    # Required due to OpenShift magic
+    securityContext:
+      runAsUser: null

infrastructure/sources/zalando-postgres.yaml

+apiVersion: source.toolkit.fluxcd.io/v1beta1
+kind: HelmRepository
+metadata:
+  name: zalando-postgres-operator
+spec:
+  interval: 30m
+  url: https://opensource.zalando.com/postgres-operator/charts/postgres-operator/