Align engine API timeouts with spec (#3470)

## Proposed Changes

Match the timeouts from the `execution-apis` spec. Our existing values were already quite close so I don't imagine this change to be very disruptive.

The spec sets the timeout for `engine_getPayloadV1` to only 1 second, but we were already using a longer value of 2 seconds. I've kept the 2 second timeout as I don't think there's any need to fail faster when producing a payload.

There's no timeout specified for `eth_syncing` so I've matched it to the shortest timeout from the spec (1 second). I think the previous value of 250ms was likely too low and could have been contributing to spurious timeouts, particularly for remote ELs.

## Additional Info

The timeouts are defined on each endpoint in this document: https://github.com/ethereum/execution-apis/blob/main/src/engine/specification.md

beacon_node/execution_layer/src/engine_api/http.rs

@@ -26,21 +26,20 @@ pub const ETH_GET_BLOCK_BY_HASH: &str = "eth_getBlockByHash";
 pub const ETH_GET_BLOCK_BY_HASH_TIMEOUT: Duration = Duration::from_secs(1);
 
 pub const ETH_SYNCING: &str = "eth_syncing";
-pub const ETH_SYNCING_TIMEOUT: Duration = Duration::from_millis(250);
+pub const ETH_SYNCING_TIMEOUT: Duration = Duration::from_secs(1);
 
 pub const ENGINE_NEW_PAYLOAD_V1: &str = "engine_newPayloadV1";
-pub const ENGINE_NEW_PAYLOAD_TIMEOUT: Duration = Duration::from_secs(6);
+pub const ENGINE_NEW_PAYLOAD_TIMEOUT: Duration = Duration::from_secs(8);
 
 pub const ENGINE_GET_PAYLOAD_V1: &str = "engine_getPayloadV1";
 pub const ENGINE_GET_PAYLOAD_TIMEOUT: Duration = Duration::from_secs(2);
 
 pub const ENGINE_FORKCHOICE_UPDATED_V1: &str = "engine_forkchoiceUpdatedV1";
-pub const ENGINE_FORKCHOICE_UPDATED_TIMEOUT: Duration = Duration::from_secs(6);
+pub const ENGINE_FORKCHOICE_UPDATED_TIMEOUT: Duration = Duration::from_secs(8);
 
 pub const ENGINE_EXCHANGE_TRANSITION_CONFIGURATION_V1: &str =
     "engine_exchangeTransitionConfigurationV1";
-pub const ENGINE_EXCHANGE_TRANSITION_CONFIGURATION_V1_TIMEOUT: Duration =
-    Duration::from_millis(500);
+pub const ENGINE_EXCHANGE_TRANSITION_CONFIGURATION_V1_TIMEOUT: Duration = Duration::from_secs(1);
 
 /// This error is returned during a `chainId` call by Geth.
 pub const EIP155_ERROR_STR: &str = "chain not synced beyond EIP-155 replay-protection fork block";