Clean capella (#4019)

## Issue Addressed

Cleans up all the remnants of 4844 in capella. This makes sure when 4844 is reviewed there is nothing we are missing because it got included here 

## Proposed Changes

drop a bomb on every 4844 thing 

## Additional Info

Merge process I did (locally) is as follows:
- squash merge to produce one commit
- in new branch off unstable with the squashed commit create a `git revert HEAD` commit
- merge that new branch onto 4844 with `--strategy ours`
- compare local 4844 to remote 4844 and make sure the diff is empty
- enjoy

Co-authored-by: Paul Hauner <paul@paulhauner.com>

consensus/state_processing/src/upgrade/eip4844.rs

@@ -1,75 +0,0 @@
-use std::mem;
-use types::{BeaconState, BeaconStateEip4844, BeaconStateError as Error, ChainSpec, EthSpec, Fork};
-
-/// Transform a `Capella` state into an `Eip4844` state.
-pub fn upgrade_to_eip4844<E: EthSpec>(
-    pre_state: &mut BeaconState<E>,
-    spec: &ChainSpec,
-) -> Result<(), Error> {
-    let epoch = pre_state.current_epoch();
-    let pre = pre_state.as_capella_mut()?;
-
-    let previous_fork_version = pre.fork.current_version;
-
-    // Where possible, use something like `mem::take` to move fields from behind the &mut
-    // reference. For other fields that don't have a good default value, use `clone`.
-    //
-    // Fixed size vectors get cloned because replacing them would require the same size
-    // allocation as cloning.
-    let post = BeaconState::Eip4844(BeaconStateEip4844 {
-        // Versioning
-        genesis_time: pre.genesis_time,
-        genesis_validators_root: pre.genesis_validators_root,
-        slot: pre.slot,
-        fork: Fork {
-            previous_version: previous_fork_version,
-            current_version: spec.eip4844_fork_version,
-            epoch,
-        },
-        // History
-        latest_block_header: pre.latest_block_header.clone(),
-        block_roots: pre.block_roots.clone(),
-        state_roots: pre.state_roots.clone(),
-        historical_roots: mem::take(&mut pre.historical_roots),
-        // Eth1
-        eth1_data: pre.eth1_data.clone(),
-        eth1_data_votes: mem::take(&mut pre.eth1_data_votes),
-        eth1_deposit_index: pre.eth1_deposit_index,
-        // Registry
-        validators: mem::take(&mut pre.validators),
-        balances: mem::take(&mut pre.balances),
-        // Randomness
-        randao_mixes: pre.randao_mixes.clone(),
-        // Slashings
-        slashings: pre.slashings.clone(),
-        // `Participation
-        previous_epoch_participation: mem::take(&mut pre.previous_epoch_participation),
-        current_epoch_participation: mem::take(&mut pre.current_epoch_participation),
-        // Finality
-        justification_bits: pre.justification_bits.clone(),
-        previous_justified_checkpoint: pre.previous_justified_checkpoint,
-        current_justified_checkpoint: pre.current_justified_checkpoint,
-        finalized_checkpoint: pre.finalized_checkpoint,
-        // Inactivity
-        inactivity_scores: mem::take(&mut pre.inactivity_scores),
-        // Sync committees
-        current_sync_committee: pre.current_sync_committee.clone(),
-        next_sync_committee: pre.next_sync_committee.clone(),
-        // Execution
-        latest_execution_payload_header: pre.latest_execution_payload_header.upgrade_to_eip4844(),
-        // Capella
-        next_withdrawal_index: pre.next_withdrawal_index,
-        next_withdrawal_validator_index: pre.next_withdrawal_validator_index,
-        historical_summaries: pre.historical_summaries.clone(),
-        // Caches
-        total_active_balance: pre.total_active_balance,
-        committee_caches: mem::take(&mut pre.committee_caches),
-        pubkey_cache: mem::take(&mut pre.pubkey_cache),
-        exit_cache: mem::take(&mut pre.exit_cache),
-        tree_hash_cache: mem::take(&mut pre.tree_hash_cache),
-    });
-
-    *pre_state = post;
-
-    Ok(())
-}