primitives: use alloy BlockWithParent

[tcoratger]

Describe the feature

Now that alloy-rs/alloy#1650 has been merged, after the next release of alloy, we will be able to use directly the BlockWithParent alloy type and remove the redundant definition from reth here

reth/crates/primitives-traits/src/header/sealed.rs

Lines 14 to 21 in d9ed07a

	/// A helper struct to store the block number/hash and its parent hash.
	#[derive(Debug, Clone, PartialEq, Eq, Hash, Serialize, Deserialize)]
	pub struct BlockWithParent {
	/// Parent hash.
	pub parent: B256,
	/// Block number/hash.
	pub block: BlockNumHash,
	}

Additional context

No response