Copy All Field Tries For Late Blocks (#12461)

* add new thing

* only have it for late blocks

* comments

* change to lock

* add test

* Update beacon-chain/state/state-native/state_test.go

---------

Co-authored-by: Radosław Kapka <rkapka@wp.pl>

beacon-chain/blockchain/process_block.go

@@ -713,6 +713,9 @@ func (s *Service) lateBlockTasks(ctx context.Context) {
 	if lastState == nil {
 		lastRoot, lastState = headRoot[:], headState
 	}
+	// Copy all the field tries in our cached state in the event of late
+	// blocks.
+	lastState.CopyAllTries()
 	if err = transition.UpdateNextSlotCache(ctx, lastRoot, lastState); err != nil {
 		log.WithError(err).Debug("could not update next slot state cache")
 	}