Remove serde derive references (#4830)

* remove remaining uses of serde_derive

* fix lockfile

---------

Co-authored-by: João Oliveira <hello@jxs.pt>

common/eth2_interop_keypairs/Cargo.toml

@@ -13,7 +13,6 @@ ethereum_hashing = { workspace = true }
 hex = { workspace = true }
 serde_yaml = { workspace = true }
 serde = { workspace = true }
-serde_derive = "1.0.116"
 bls = { workspace = true }
 
 [dev-dependencies]

common/eth2_interop_keypairs/src/lib.rs

@@ -22,7 +22,7 @@ extern crate lazy_static;
 use bls::{Keypair, PublicKey, SecretKey};
 use ethereum_hashing::hash;
 use num_bigint::BigUint;
-use serde_derive::{Deserialize, Serialize};
+use serde::{Deserialize, Serialize};
 use std::convert::TryInto;
 use std::fs::File;
 use std::path::PathBuf;