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>

beacon_node/beacon_chain/src/beacon_proposer_cache.rs

@@ -18,10 +18,9 @@ use state_processing::state_advance::partial_state_advance;
 use std::num::NonZeroUsize;
 use std::sync::Arc;
 use tracing::instrument;
+use typenum::Unsigned;
 use types::non_zero_usize::new_non_zero_usize;
-use types::{
-    BeaconState, BeaconStateError, ChainSpec, Epoch, EthSpec, Fork, Hash256, Slot, Unsigned,
-};
+use types::{BeaconState, BeaconStateError, ChainSpec, Epoch, EthSpec, Fork, Hash256, Slot};
 
 /// The number of sets of proposer indices that should be cached.
 const CACHE_SIZE: NonZeroUsize = new_non_zero_usize(16);