Enable lints for tests only running optimized (#6664)

* enable linting optimized-only tests

* fix automatically fixable or obvious lints

* fix suspicious_open_options by removing manual options

* fix `await_holding_lock`s

* avoid failing lint due to now disabled `#[cfg(debug_assertions)]`

* reduce future sizes in tests

* fix accidently flipped assert logic

* restore holding lock for web3signer download

* Merge branch 'unstable' into lint-opt-tests

beacon_node/beacon_chain/tests/tests.rs

@@ -170,7 +170,7 @@ async fn find_reorgs() {
 
     harness
         .extend_chain(
-            num_blocks_produced as usize,
+            num_blocks_produced,
             BlockStrategy::OnCanonicalHead,
             // No need to produce attestations for this test.
             AttestationStrategy::SomeValidators(vec![]),
@@ -203,7 +203,7 @@ async fn find_reorgs() {
     assert_eq!(
         find_reorg_slot(
             &harness.chain,
-            &head_state,
+            head_state,
             harness.chain.head_beacon_block().canonical_root()
         ),
         head_slot
@@ -503,7 +503,6 @@ async fn unaggregated_attestations_added_to_fork_choice_some_none() {
         .unwrap();
 
     let validator_slots: Vec<(usize, Slot)> = (0..VALIDATOR_COUNT)
-        .into_iter()
         .map(|validator_index| {
             let slot = state
                 .get_attestation_duties(validator_index, RelativeEpoch::Current)