refactor: only use one (direction) flag for identifying payment

lnbits/core/crud.py

@@ -455,20 +455,14 @@ async def update_payment_extra(
     payment_hash: str,
     extra: dict,
     outgoing: bool = False,
-    incoming: bool = False,
     conn: Optional[Connection] = None,
 ) -> None:
     """
     Only update the `extra` field for the payment.
     Old values in the `extra` JSON object will be kept unless the new `extra` overwrites them.
     """
-    amount_clause = ""
 
-    if outgoing != incoming:
-        if outgoing:
-            amount_clause = "AND amount < 0"
-        else:
-            amount_clause = "AND amount > 0"
+    amount_clause = "AND amount < 0" if outgoing else "AND amount > 0"
 
     row = await (conn or db).fetchone(
         f"SELECT hash, extra from apipayments WHERE hash = ? {amount_clause}",