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>

testing/web3signer_tests/src/lib.rs

@@ -20,9 +20,11 @@ mod tests {
     use account_utils::validator_definitions::{
         SigningDefinition, ValidatorDefinition, ValidatorDefinitions, Web3SignerDefinition,
     };
+    use bls::{AggregateSignature, Keypair, PublicKeyBytes, SecretKey, Signature};
     use eth2::types::FullBlockContents;
     use eth2_keystore::KeystoreBuilder;
     use eth2_network_config::Eth2NetworkConfig;
+    use fixed_bytes::FixedBytesExtended;
     use initialized_validators::{
         InitializedValidators, load_pem_certificate, load_pkcs12_identity,
     };
@@ -32,6 +34,7 @@ mod tests {
     use serde::Serialize;
     use slashing_protection::{SLASHING_PROTECTION_FILENAME, SlashingDatabase};
     use slot_clock::{SlotClock, TestingSlotClock};
+    use ssz_types::BitList;
     use std::env;
     use std::fmt::Debug;
     use std::fs::{self, File};