Add Electra fork boilerplate (#5122)

* Add Electra fork boilerplate

* Remove electra from spec tests

* Fix tests

* Remove sneaky log file

* Fix more tests

* Fix even more tests and add suggestions

* Remove unrelated lcli addition

* Update more tests

* Merge branch 'unstable' into electra

* Add comment for test-suite lcli override

* Merge branch 'unstable' into electra

* Cleanup

* Merge branch 'unstable' into electra

* Apply suggestions

* Merge branch 'unstable' into electra

* Merge sigp/unstable into electra

* Merge branch 'unstable' into electra

consensus/state_processing/src/per_slot_processing.rs

@@ -1,5 +1,6 @@
 use crate::upgrade::{
     upgrade_to_altair, upgrade_to_bellatrix, upgrade_to_capella, upgrade_to_deneb,
+    upgrade_to_electra,
 };
 use crate::{per_epoch_processing::EpochProcessingSummary, *};
 use safe_arith::{ArithError, SafeArith};
@@ -61,10 +62,14 @@ pub fn per_slot_processing<T: EthSpec>(
         if spec.capella_fork_epoch == Some(state.current_epoch()) {
             upgrade_to_capella(state, spec)?;
         }
-        // Deneb
+        // Deneb.
         if spec.deneb_fork_epoch == Some(state.current_epoch()) {
             upgrade_to_deneb(state, spec)?;
         }
+        // Electra.
+        if spec.electra_fork_epoch == Some(state.current_epoch()) {
+            upgrade_to_electra(state, spec)?;
+        }
     }
 
     Ok(summary)