Increase timeouts for EEs (#3125)

## Issue Addressed

NA

## Proposed Changes

In the first Goerli shadow-fork, Lighthouse was getting timeouts from Geth which prevented the LH+Geth pair from progressing.

There's not a whole lot of information I can use to set these timeouts. The most interesting pieces of information I have are quotes from Marius from Geth:

- *"Fcu also needs to construct the block which can take 2sec"* ([Discord](https://discord.com/channels/595666850260713488/910910348922589184/958006487052066836))
- *"2 sec should be ok for new payload, weird that it times out"* ([Discord](https://discord.com/channels/595666850260713488/910910348922589184/958006487052066836))

I don't think we should be so worried about getting these timeouts correct now. No one really knows how long the various EEs are going to take, it's a bit too early in development. With these changes I'm giving some headroom so that we don't fail just because EEs are quite optimized enough. I've set the value to 6s (half a mainnet slot), since I think anything beyond 6s is an interesting problem that we want to know about sooner rather than later.

## Additional Info

NA

beacon_node/execution_layer/src/engine_api/http.rs

@@ -29,13 +29,13 @@ pub const ETH_SYNCING: &str = "eth_syncing";
 pub const ETH_SYNCING_TIMEOUT: Duration = Duration::from_millis(250);
 
 pub const ENGINE_NEW_PAYLOAD_V1: &str = "engine_newPayloadV1";
-pub const ENGINE_NEW_PAYLOAD_TIMEOUT: Duration = Duration::from_secs(2);
+pub const ENGINE_NEW_PAYLOAD_TIMEOUT: Duration = Duration::from_secs(6);
 
 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_millis(500);
+pub const ENGINE_FORKCHOICE_UPDATED_TIMEOUT: Duration = Duration::from_secs(6);
 
 pub const ENGINE_EXCHANGE_TRANSITION_CONFIGURATION_V1: &str =
     "engine_exchangeTransitionConfigurationV1";