Ensure PodSecurityPolicy controller is enabled on Google Container Cluster

PodSecurityPolicy controller has been disabled on the Google Container Cluster. PodSecurityPolicy controller allows you to better control security of your pods.

Kubernetes has officially deprecated PodSecurityPolicy in version 1.21. PodSecurityPolicy will be removed in version 1.25.

In Terraform -

1. In the google_container_cluster resource, ensure that pod_security_policy_config block attribute is added with enabled attribute set to true.

References:
https://registry.terraform.io/providers/hashicorp/google/3.78.0/docs/resources/container_cluster
https://cloud.google.com/kubernetes-engine/docs/how-to/pod-security-policies?hl=en