Update compute_el_header_block_hash for EIP-7685

[jtraglia]

Reference: https://eips.ethereum.org/EIPS/eip-7685

This PR does the following:

• Consolidate deposit_receipts and withdrawal_requests into requests.
• When encoding those two types, prefix with type (0x00 and 0x01).
• Encode with non-null parent_beacon_root.
  • A null parent_beacon_root causes issues when requests_root is not null.
  • I believe this field was accidentally overlooked before.
• Set payload.withdrawal_requests = [] in build_empty_execution_payload.

I noticed these issues when looking into why the block hash differed from Geth.

[jtraglia]

@lightclient I would appreciate your review but I can't select you as a reviewer.

[mkalinin]

The logic looks correct to me. One nit: get_deposit_receipt_rlp (same with withdrawal requests) returns Request encoding which is not an RLP because of the type byte at the beginning, consider renaming these methods to reflect their actual semantics.

[jtraglia]

consider renaming these methods to reflect their actual semantics.

Ah yes, you're right. Thanks for pointing this out! I took this approach.

[hwwhww]

Note: if #3757 gets merged, we should rename it in this PR too.

[hwwhww]

@jtraglia I fixed the conflicts and added lines for ConsolidationRequest. Could you take a look?

[jtraglia]

@jtraglia I fixed the conflicts and added lines for ConsolidationRequest. Could you take a look?

@hwwhww So get_withdrawal_request_rlp_bytes and get_consolidation_request_rlp_bytes are both prefixed with 0x01 now, these should be different. And get_deposit_request_rlp_bytes doesn't have a prefix byte anymore.

I'm guessing deposit_requests=0, withdrawal_requests=1, and consolidation_requests=2 but I'm not sure.

[hwwhww]

@jtraglia you're right! I forget to update the prefix when copy-pasting.