Require Multiple Replicas in CEL expressions

apiVersion: kyverno.io/v1
kind: ClusterPolicy
metadata:
  name: deployment-has-multiple-replicas
  annotations:
    policies.kyverno.io/title: Require Multiple Replicas in CEL expressions
    policies.kyverno.io/category: Sample in CEL
    policies.kyverno.io/severity: medium
    policies.kyverno.io/subject: Deployment
    policies.kyverno.io/minversion: 1.11.0
    kyverno.io/kubernetes-version: 1.26-1.27
    policies.kyverno.io/description: Deployments with a single replica cannot be highly available and thus the application may suffer downtime if that one replica goes down. This policy validates that Deployments have more than one replica.
spec:
  validationFailureAction: Audit
  background: true
  rules:
    - name: deployment-has-multiple-replicas
      match:
        any:
          - resources:
              kinds:
                - Deployment
              operations:
                - CREATE
                - UPDATE
      validate:
        cel:
          expressions:
            - expression: object.spec.replicas > 1
              message: Deployments should have more than one replica to ensure availability.