modules/vpc-sc: google_access_context_manager_service_perimeter add support for method_selectors/permission

[LudovicEmo]

Hello,

modules/vpc-sc is already supporting method_selectors/method for the google_access_context_manager_service_perimeter resource.
This PR adds support for method_selectors/permission.

Example:

resource "google_access_context_manager_service_perimeter" "sp" {
  [REDACTED]
  spec {
    egress_policies { 
      egress_to {
        resources = [
          "projects/111111111111",
        ]
        operations {
          service_name = "bigquery.googleapis.com" 
          method_selectors {
            permission = "bigquery.vpcsc.importData"
          }
        }
    }
  }
  [REDACTED]
}

Reference: https://registry.terraform.io/providers/hashicorp/google/latest/docs/resources/access_context_manager_service_perimeters#permission

[google-cla]

Thanks for your pull request! It looks like this may be your first contribution to a Google open source project. Before we can look at your pull request, you'll need to sign a Contributor License Agreement (CLA).

View this failed invocation of the CLA check for more information.

For the most up to date status, view the checks section at the bottom of the pull request.

[ludoo]

Sorry it took us so long to review this, and thanks for the addition!