Merge pull request #2 from conduition/dlc

avoid re-settling already settled DLC

cashu/mint/db/write.py

@@ -316,6 +316,7 @@ async def _settle_dlc(
                             dlc_root=settlement.dlc_root,
                             details="DLC already settled"
                         ))
+                        continue
 
                     assert settlement.outcome
                     await self.crud.set_dlc_settled_and_debts(settlement.dlc_root, settlement.outcome.P, self.db, conn)