Remove all prod eth1 related code (#7133)

N/A


  After the electra fork which includes EIP 6110, the beacon node no longer needs the eth1 bridging mechanism to include new deposits as they are provided by the EL as a `deposit_request`. So after electra + a transition period where the finalized bridge deposits pre-fork are included through the old mechanism, we no longer need the elaborate machinery we had to get deposit contract data from the execution layer.

Since holesky has already forked to electra and completed the transition period, this PR basically checks to see if removing all the eth1 related logic leads to any surprises.

beacon_node/http_api/src/test_utils.rs

@@ -188,8 +188,6 @@ pub async fn create_api_server_with_config<T: BeaconChainTypes>(
     }));
     *network_globals.sync_state.write() = SyncState::Synced;
 
-    let eth1_service = eth1::Service::new(eth1::Config::default(), chain.spec.clone()).unwrap();
-
     let beacon_processor_config = BeaconProcessorConfig {
         // The number of workers must be greater than one. Tests which use the
         // builder workflow sometimes require an internal HTTP request in order
@@ -236,7 +234,6 @@ pub async fn create_api_server_with_config<T: BeaconChainTypes>(
         network_senders: Some(network_senders),
         network_globals: Some(network_globals),
         beacon_processor_send: Some(beacon_processor_send),
-        eth1_service: Some(eth1_service),
         sse_logging_components: None,
     });