Remove consensus/types re-exports (#8540)

There are certain crates which we re-export within `types` which creates a fragmented DevEx, where there are various ways to import the same crates.

```rust
// consensus/types/src/lib.rs
pub use bls::{
AggregatePublicKey, AggregateSignature, Error as BlsError, Keypair, PUBLIC_KEY_BYTES_LEN,
PublicKey, PublicKeyBytes, SIGNATURE_BYTES_LEN, SecretKey, Signature, SignatureBytes,
get_withdrawal_credentials,
};
pub use context_deserialize::{ContextDeserialize, context_deserialize};
pub use fixed_bytes::FixedBytesExtended;
pub use milhouse::{self, List, Vector};
pub use ssz_types::{BitList, BitVector, FixedVector, VariableList, typenum, typenum::Unsigned};
pub use superstruct::superstruct;
```

This PR removes these re-exports and makes it explicit that these types are imported from a non-`consensus/types` crate.


Co-Authored-By: Mac L <mjladson@pm.me>

consensus/proto_array/src/proto_array.rs

@@ -1,5 +1,6 @@
 use crate::error::InvalidBestNodeInfo;
 use crate::{Block, ExecutionStatus, JustifiedBalances, error::Error};
+use fixed_bytes::FixedBytesExtended;
 use serde::{Deserialize, Serialize};
 use ssz::Encode;
 use ssz::four_byte_option_impl;
@@ -7,8 +8,8 @@ use ssz_derive::{Decode, Encode};
 use std::collections::{HashMap, HashSet};
 use superstruct::superstruct;
 use types::{
-    AttestationShufflingId, ChainSpec, Checkpoint, Epoch, EthSpec, ExecutionBlockHash,
-    FixedBytesExtended, Hash256, Slot,
+    AttestationShufflingId, ChainSpec, Checkpoint, Epoch, EthSpec, ExecutionBlockHash, Hash256,
+    Slot,
 };
 
 // Define a "legacy" implementation of `Option<usize>` which uses four bytes for encoding the union