Fix clippy warnings (#813)

* Clippy account manager

* Clippy account_manager

* Clippy beacon_node/beacon_chain

* Clippy beacon_node/client

* Clippy beacon_node/eth1

* Clippy beacon_node/eth2-libp2p

* Clippy beacon_node/genesis

* Clippy beacon_node/network

* Clippy beacon_node/rest_api

* Clippy beacon_node/src

* Clippy beacon_node/store

* Clippy eth2/lmd_ghost

* Clippy eth2/operation_pool

* Clippy eth2/state_processing

* Clippy eth2/types

* Clippy eth2/utils/bls

* Clippy eth2/utils/cahced_tree_hash

* Clippy eth2/utils/deposit_contract

* Clippy eth2/utils/eth2_interop_keypairs

* Clippy eth2/utils/eth2_testnet_config

* Clippy eth2/utils/lighthouse_metrics

* Clippy eth2/utils/ssz

* Clippy eth2/utils/ssz_types

* Clippy eth2/utils/tree_hash_derive

* Clippy lcli

* Clippy tests/beacon_chain_sim

* Clippy validator_client

* Cargo fmt

beacon_node/beacon_chain/src/test_utils.rs

@@ -173,7 +173,7 @@ impl<E: EthSpec> BeaconChainHarness<DiskHarnessType<E>> {
 
         let chain = BeaconChainBuilder::new(eth_spec_instance)
             .logger(log.clone())
-            .custom_spec(spec.clone())
+            .custom_spec(spec)
             .store(store.clone())
             .store_migrator(<BlockingMigrator<_> as Migrate<_, E>>::new(store))
             .resume_from_db(Eth1Config::default())
@@ -236,7 +236,6 @@ where
             self.chain
                 .state_at_slot(state_slot)
                 .expect("should find state for slot")
-                .clone()
         };
 
         // Determine the first slot where a block should be built.