chore(deps): update postgresql-ha docker tag to v12 (#528)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [postgresql-ha](https://github.com/bitnami/charts) ([source](https://github.com/bitnami/charts/tree/HEAD/bitnami/postgresql-ha)) | major | `11.9.4` -> `12.3.1` |

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Co-authored-by: pat-s <patrick.schratz@gmail.com>
Reviewed-on: https://gitea.com/gitea/helm-chart/pulls/528
Co-authored-by: Renovate Bot <renovate-bot@gitea.com>
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unittests/dependency-major-image-check.yaml

@@ -15,7 +15,7 @@ tests:
         matchRegex:
           path: spec.template.spec.containers[0].image
           # IN CASE OF AN INTENTIONAL MAJOR BUMP, ADJUST THIS TEST
-          pattern: ^docker.io/bitnami/postgresql-repmgr:15.+$
+          pattern: ^docker.io/bitnami/postgresql-repmgr:16.+$
   - it: "[postgresql] ensures we detect major image version upgrades"
     template: charts/postgresql/templates/primary/statefulset.yaml
     set: