feat: Add sensitive flag for MySQL module outputs (#303)

running terraform plan on MySQL module was generating errors
because the values in these outputs are considered sensitive.

Co-authored-by: Artem Vovk <avovk@recurly.com>
Co-authored-by: Bharath KKB <bharathkrishnakb@gmail.com>

modules/mysql/outputs.tf

@@ -117,14 +117,17 @@ output "private_ip_address" {
 output "primary" {
   value       = google_sql_database_instance.default
   description = "The `google_sql_database_instance` resource representing the primary instance"
+  sensitive   = true
 }
 
 output "replicas" {
   value       = values(google_sql_database_instance.replicas)
   description = "A list of `google_sql_database_instance` resources representing the replicas"
+  sensitive   = true
 }
 
 output "instances" {
   value       = concat([google_sql_database_instance.default], values(google_sql_database_instance.replicas))
   description = "A list of all `google_sql_database_instance` resources we've created"
+  sensitive   = true
 }