Rename Merge to Bellatrix (#5601)

* Rename Merge to Bellatrix

* Remove tree-hash-cache which got readded from the rebase

consensus/state_processing/src/per_block_processing/process_operations.rs

@@ -273,7 +273,7 @@ pub fn process_attestations<E: EthSpec, Payload: AbstractExecPayload<E>>(
             )?;
         }
         BeaconBlockBodyRef::Altair(_)
-        | BeaconBlockBodyRef::Merge(_)
+        | BeaconBlockBodyRef::Bellatrix(_)
         | BeaconBlockBodyRef::Capella(_)
         | BeaconBlockBodyRef::Deneb(_)
         | BeaconBlockBodyRef::Electra(_) => {

consensus/state_processing/src/per_block_processing/signature_sets.rs

@@ -390,7 +390,7 @@ where
     let domain = match state {
         BeaconState::Base(_)
         | BeaconState::Altair(_)
-        | BeaconState::Merge(_)
+        | BeaconState::Bellatrix(_)
         | BeaconState::Capella(_) => spec.get_domain(
             exit.epoch,
             Domain::VoluntaryExit,

consensus/state_processing/src/per_block_processing/verify_attestation.rs

@@ -35,7 +35,7 @@ pub fn verify_attestation_for_block_inclusion<'ctxt, E: EthSpec>(
     match state {
         BeaconState::Base(_)
         | BeaconState::Altair(_)
-        | BeaconState::Merge(_)
+        | BeaconState::Bellatrix(_)
         | BeaconState::Capella(_) => {
             verify!(
                 state.slot() <= data.slot.safe_add(E::slots_per_epoch())?,