feat: update submit signature grace period

Author: janezicmatej

observer/validation/fdc.py

@@ -177,7 +177,7 @@ def check_submit_signatures(
 
     if submit_signatures is not None:
         deadline = max(
-            round.voting_epoch.next.start_s + 55,
+            round.voting_epoch.next.start_s + 60,
             (finalization and finalization.timestamp) or 0,
         )
 

observer/validation/ftso.py

@@ -185,7 +185,7 @@ def check_submit_signatures(
 
     if submit_signatures is not None:
         deadline = max(
-            round.voting_epoch.next.start_s + 55,
+            round.voting_epoch.next.start_s + 60,
             (finalization and finalization.timestamp) or 0,
         )
 

observer/voting_round.py

@@ -249,7 +249,7 @@ def finalize(self, block: BlockData) -> list[VotingRound]:
                 self.rounds.pop(k, None)
                 continue
 
-            # 55 is submit sigs deadline, 10 is relay grace, 10 is additional buffer
+            # need to wait until end of epoch to collect all signatures
             round_completed = k.next.end_s < block["timestamp"]
 
             if round_completed: