cnpg: upgrade operator to 1.27.1 (chart 0.26.1)

One minor at a time from 1.25.1 to 1.30.1, see docs/upgrade-k8s-1.33.md. In-place instance manager updates keep the database pods running.

apps/templates/cloudnativepg-helm.yaml

@@ -10,7 +10,7 @@ spec:
   source:
     chart: cloudnative-pg
     repoURL: https://cloudnative-pg.github.io/charts
-    targetRevision: 0.25.0
+    targetRevision: 0.26.1
     helm:
       values: |
         config: