Fix indempotence issue with policy attach

src/minio.rs

@@ -531,6 +531,15 @@ impl MinioService {
 
     /// Attach a user to a policy
     pub async fn policy_attach_user(&self, user: &MinioUser, policy: &str) -> anyhow::Result<()> {
+        // Check if the policy has already been attached to the user
+        if self
+            .policy_attach_get_user_list(user)
+            .await?
+            .contains(&policy.to_string())
+        {
+            return Ok(());
+        }
+
         let res = self
             .exec_mc_cmd::<BasicMinioResult>(&[
                 "admin",