Update quest.py (#997)

small typo fix

cryptofeed/backends/quest.py

@@ -72,7 +72,7 @@ def __init__(self, *args, depth=10, **kwargs):
         self.depth = depth
 
     async def __call__(self, book, receipt_timestamp: float):
-        vals = ','.join([f"bid_{i}_price={book.book.bids.index(i)[0]},bid_{i}_size={book.book.bids.index(i)[1]}" for i in range(self.depth)] + [f"ask{i}_price={book.book.asks.index(i)[0]},ask_{i}_size={book.book.asks.index(i)[1]}" for i in range(self.depth)])
+        vals = ','.join([f"bid_{i}_price={book.book.bids.index(i)[0]},bid_{i}_size={book.book.bids.index(i)[1]}" for i in range(self.depth)] + [f"ask_{i}_price={book.book.asks.index(i)[0]},ask_{i}_size={book.book.asks.index(i)[1]}" for i in range(self.depth)])
         timestamp = book.timestamp
         receipt_timestamp_int = int(receipt_timestamp * 1_000_000)
         timestamp_int = int(timestamp * 1_000_000_000) if timestamp is not None else receipt_timestamp_int * 1000