Capella beacon state (#11141)

* fork

* types

* cloners

* getters

* remove CapellaBlind from fork

* hasher

* setters

* spec params, config tests

* generate ssz

* executionPayloadHeaderCapella

* proto state

* BeaconStateCapella SSZ

* saving state

* configfork

* BUILD files

* fix RealPosition

* fix hasher

* SetLatestExecutionPayloadHeaderCapella

* fix error message

* reduce complexity of saveStatesEfficientInternal

* add latestExecutionPayloadHeaderCapella to minimal state

* halway done interface

* remove withdrawal methods

* merge setters

* change signatures for v1 and v2

* fixing errors pt. 1

* paylod_test fixes

* fix everything

* remove unused func

* fix tests

* state_trie_test improvements

* in progress...

* hasher test

* fix configs

* simplify hashing

* Revert "fix configs"

This reverts commit bcae2825fc.

* remove capella from config test

* unify locking

* review

* hashing

* fixes

Co-authored-by: terencechain <terence@prysmaticlabs.com>
Co-authored-by: Raul Jordan <raul@prysmaticlabs.com>

runtime/version/fork.go

@@ -4,6 +4,7 @@ const (
 	Phase0 = iota
 	Altair
 	Bellatrix
+	Capella
 )
 
 func String(version int) string {
@@ -14,6 +15,8 @@ func String(version int) string {
 		return "altair"
 	case Bellatrix:
 		return "bellatrix"
+	case Capella:
+		return "capella"
 	default:
 		return "unknown version"
 	}