* specs: Update executePayloadV1 to newPayloadV1

Just updating the name in the specs. This has already been changed
in the code.

* specs: Deposits -> Withdrawals spec clarification

Wording was incorrect.

* specs: Remove unnecessary cast

The casts from bytes32 -> uint256 -> bytes32 is not needed.

* specs: no alias on withdrawals

* fix lint

* specs: fix parentheses
Co-authored-by: Diederik Loerakker <proto@protolambda.com>
Co-authored-by: Maurelian <maurelian@protonmail.ch>
Co-authored-by: Diederik Loerakker <proto@protolambda.com>