test: add parse pk test

ethers-signers/src/wallet/private_key.rs

@@ -161,6 +161,12 @@ mod tests {
     use ethers_core::types::Address;
     use tempfile::tempdir;
 
+    #[test]
+    fn parse_pk() {
+        let s = "6f142508b4eea641e33cb2a0161221105086a84584c74245ca463a49effea30b";
+        let pk: Wallet<SigningKey> = s.parse().unwrap();
+    }
+
     #[tokio::test]
     async fn encrypted_json_keystore() {
         // create and store a random encrypted JSON keystore in this directory