Fix lint

rust/hyperlane-base/src/settings/signers.rs

@@ -3,7 +3,7 @@ use std::time::Duration;
 use async_trait::async_trait;
 use ethers::prelude::{AwsSigner, LocalWallet};
 use eyre::{bail, eyre, Context, Report};
-use rusoto_core::{HttpClient, Region, HttpConfig};
+use rusoto_core::{HttpClient, HttpConfig, Region};
 use rusoto_kms::KmsClient;
 use serde::Deserialize;
 use tracing::instrument;
@@ -107,6 +107,7 @@ impl BuildableWithSignerConf for hyperlane_ethereum::Signers {
             )),
             SignerConf::Aws { id, region } => {
                 let mut config = HttpConfig::new();
+                // see https://github.com/hyperium/hyper/issues/2136#issuecomment-589345238
                 config.pool_idle_timeout(Duration::from_secs(20));
                 let client = KmsClient::new_with_client(
                     rusoto_core::Client::new_with(