Fix tree-states tests after latest update (#5528)

* Fix clippy

* Fix beacon chain tests

* Comment out dodgy iterator test

* Fix imports for beta compiler

beacon_node/execution_layer/src/engine_api.rs

@@ -18,7 +18,6 @@ use pretty_reqwest_error::PrettyReqwestError;
 use reqwest::StatusCode;
 use serde::{Deserialize, Serialize};
 use ssz_types::FixedVector;
-use std::convert::TryFrom;
 use strum::IntoStaticStr;
 use superstruct::superstruct;
 pub use types::{

beacon_node/execution_layer/src/engine_api/json_structures.rs

@@ -5,10 +5,7 @@ use strum::EnumString;
 use superstruct::superstruct;
 use types::beacon_block_body::KzgCommitments;
 use types::blob_sidecar::BlobsList;
-use types::{
-    EthSpec, ExecutionBlockHash, ExecutionPayload, ExecutionPayloadCapella, ExecutionPayloadDeneb,
-    ExecutionPayloadMerge, Transactions, Unsigned, VariableList, Withdrawal,
-};
+use types::Unsigned;
 
 #[derive(Debug, PartialEq, Serialize, Deserialize)]
 #[serde(rename_all = "camelCase")]