invalid spec initContainers startupProbe Forbidden with barman cloud plugin

Cluster pod does not start if I add barman cloud plugin with objectstore for WAL and backup purposes, I see invalid spec initContainers startupProbe Forbidden logs in operator logs attached below

cloudnative pg operator Version
1.26 (latest patch)

What version of Kubernetes are you using?
1.30

What is your Kubernetes environment?
Cloud: Azure AKS

How did you install the operator?
Helm

**objectstore yaml**
```
apiVersion: v1
kind: Secret
metadata:
name: testcnpg-azobjectstore-secret
type: Opaque
stringData:
AZURE_CONNECTION_STRING: "DefaultEndpointsProtocol=https;AccountName=xxx;AccountKey=xxxx;EndpointSuffix=core.windows.net"
---
apiVersion: barmancloud.cnpg.io/v1
kind: ObjectStore
metadata:
name: testcnpg-azobjectstore
spec:
configuration:
destinationPath: "https://xxx.blob.core.windows.net/cnpg-backups/testcnpg"
azureCredentials:
connectionString:
name: testcnpg-azobjectstore-secret
key: AZURE_CONNECTION_STRING
wal:
compression: gzip
retentionPolicy: 30d
```

**Cluster resource**
```
apiVersion: postgresql.cnpg.io/v1
kind: Cluster
metadata:
name: testcnpg
spec:
instances: 1
imageName: ghcr.io/cloudnative-pg/postgresql:15.10
postgresql:
parameters:
shared_buffers: 256MB
log_statement: mod
log_connections: "off"
log_disconnections: "off"
bootstrap:
initdb:
database: testcnpg
plugins:
- name: barman-cloud.cloudnative-pg.io
isWALArchiver: true
parameters:
barmanObjectName: testcnpg-azobjectstore
storage:
storageClass: managed-csi
size: 1Gi
```

**operator logs**
```
{"level":"info","ts":"2025-07-14T14:01:55.17739142Z","msg":"Creating new Pod to reattach a PVC","controller":"cluster","controllerGroup":"postgresql.cnpg.io","controllerKind":"Cluster","Cluster":{"name":"testcnpg","namespace":"infra"},"namespace":"infra","name":"testcnpg","reconcileID":"b55c5ff4-acc2-48c4-96c3-419ce6c1ed9d","pod":"testcnpg-1","pvc":"testcnpg-1"}

{"level":"error","ts":"2025-07-14T14:01:55.727993328Z","msg":"Reconciler error","controller":"cluster","controllerGroup":"postgresql.cnpg.io","controllerKind":"Cluster","Cluster":{"name":"testcnpg","namespace":"infra"},"namespace":"infra","name":"testcnpg","reconcileID":"b55c5ff4-acc2-48c4-96c3-419ce6c1ed9d","error":"unable to create Pod: Pod \"testcnpg-1\" is invalid: spec.initContainers[1].startupProbe: Forbidden: may not be set for init containers without restartPolicy=Always","stacktrace":"sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller[...]).reconcileHandler\n\tpkg/mod/sigs.k8s.io/controller-runtime@v0.20.4/pkg/internal/controller/controller.go:347\nsigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller[...]).processNextWorkItem\n\tpkg/mod/sigs.k8s.io/controller-runtime@v0.20.4/pkg/internal/controller/controller.go:294\nsigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller[...]).Start.func2.2\n\tpkg/mod/sigs.k8s.io/controller-runtime@v0.20.4/pkg/internal/controller/controller.go:255"}
```

在 Kubernetes 1.30 上复现所提供的 ObjectStore 和 Cluster 清单，并检查生成的 Pod 的 initContainers。从显示 initContainers[1].startupProbe 的 operator 错误开始；当 Pod 在没有 startupProbe 被禁止的验证错误的情况下被接受时，即可认为问题已解决。

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