Describe the issue

When using multiple KMS keys for Spanner database encryption, CKV_GCP_93 check fails even when the database is properly configured with CMEK encryption.

Looking at the check implementation, it makes no effort to even try to check for the multi-key configuration.

Examples

This fails the check, even though the database is clearly configured with encryption:

resource "google_spanner_database" "multikey_pass" {
  instance = google_spanner_instance.example.name
  name     = "my-database"
  ddl = [
    "CREATE TABLE t1 (t1 INT64 NOT NULL,) PRIMARY KEY(t1)",
    "CREATE TABLE t2 (t2 INT64 NOT NULL,) PRIMARY KEY(t2)",
  ]
  deletion_protection = false
  encryption_config {
    kms_key_names = [google_kms_crypto_key.example.name]
  }
}

Version (please complete the following information):

• 3.2.351

Additional context
https://registry.terraform.io/providers/hashicorp/google/latest/docs/resources/spanner_database#nested_encryption_config