docs: added parent region tags for custom SAN examples

Author: seviet

cloud_sql/mysql_instance_custom_subject_alternative_names/main.tf

@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+# [START cloud_sql_mysql_mysql_instance_custom_subject_alternative_names_create]
 # [START cloud_sql_mysql_instance_service_identity]
 resource "google_project_service_identity" "default" {
   provider = google-beta
@@ -106,3 +107,4 @@ resource "google_sql_database_instance" "default" {
   }
 }
 # [END cloud_sql_mysql_instance_custom_subject_alternative_names]
+# [END cloud_sql_mysql_instance_custom_subject_alternative_names_create]

cloud_sql/postgres_instance_custom_subject_alternative_names/main.tf

@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+# [START cloud_sql_postgres_instance_custom_subject_alternative_names_create]
 # [START cloud_sql_postgres_instance_service_identity]
 resource "google_project_service_identity" "default" {
   provider = google-beta
@@ -106,3 +107,4 @@ resource "google_sql_database_instance" "default" {
   }
 }
 # [END cloud_sql_postgres_instance_custom_subject_alternative_names]
+# [END cloud_sql_postgres_instance_custom_subject_alternative_names_create]

cloud_sql/sqlserver_instance_custom_subject_alternative_names/main.tf

@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+# [START cloud_sql_sqlserver_instance_custom_subject_alternative_names_create]
 # [START cloud_sql_sqlserver_instance_service_identity]
 resource "google_project_service_identity" "default" {
   provider = google-beta
@@ -106,3 +107,4 @@ resource "google_sql_database_instance" "default" {
   }
 }
 # [END cloud_sql_sqlserver_instance_custom_subject_alternative_names]
+# [END cloud_sql_sqlserver_instance_custom_subject_alternative_names_create]