Remove use of ethers core (#5301)

* Remove use of ethers_core::RlpStream

* Merge branch 'unstable' of https://github.com/sigp/lighthouse into remove_use_of_ethers_core

* Remove old code

* Simplify keccak call

* Remove unused package

* Merge branch 'unstable' of https://github.com/ethDreamer/lighthouse into remove_use_of_ethers_core

* Merge branch 'unstable' into remove_use_of_ethers_core

* Run clippy

* Merge branch 'remove_use_of_ethers_core' of https://github.com/dospore/lighthouse into remove_use_of_ethers_core

* Check all cargo fmt

* Merge branch 'unstable' of https://github.com/sigp/lighthouse into remove_use_of_ethers_core

* Revert lock

* Merge branch 'unstable' of https://github.com/sigp/lighthouse into remove_use_of_ethers_core

* introduce a shim to convert between the two u256 types

* move alloy to wrokspace

* align alloy versions

* update

* update web3signer test certs

* Revert "update web3signer test certs"

This reverts commit effd5910ad.

* Consolidate alloy versions

* Delete empty file

beacon_node/execution_layer/src/engine_api/json_structures.rs

@@ -1,4 +1,5 @@
 use super::*;
+use alloy_rlp::RlpEncodable;
 use serde::{Deserialize, Serialize};
 use strum::EnumString;
 use superstruct::superstruct;
@@ -463,6 +464,24 @@ impl From<JsonWithdrawal> for Withdrawal {
         }
     }
 }
+#[derive(Debug, PartialEq, Clone, RlpEncodable)]
+pub struct EncodableJsonWithdrawal<'a> {
+    pub index: u64,
+    pub validator_index: u64,
+    pub address: &'a [u8],
+    pub amount: u64,
+}
+
+impl<'a> From<&'a JsonWithdrawal> for EncodableJsonWithdrawal<'a> {
+    fn from(json_withdrawal: &'a JsonWithdrawal) -> Self {
+        Self {
+            index: json_withdrawal.index,
+            validator_index: json_withdrawal.validator_index,
+            address: json_withdrawal.address.as_bytes(),
+            amount: json_withdrawal.amount,
+        }
+    }
+}
 
 #[superstruct(
     variants(V1, V2, V3),