Check if exchang provides bid/ask via fetch_tickers - and fail with spread filter if it doesn't.

closes #8286

freqtrade/exchange/exchange.py

@@ -69,6 +69,7 @@ class Exchange:
         # Check https://github.com/ccxt/ccxt/issues/10767 for removal of ohlcv_volume_currency
         "ohlcv_volume_currency": "base",  # "base" or "quote"
         "tickers_have_quoteVolume": True,
+        "tickers_have_bid_ask": True,  # bid / ask empty for fetch_tickers
         "tickers_have_price": True,
         "trades_pagination": "time",  # Possible are "time" or "id"
         "trades_pagination_arg": "since",

freqtrade/exchange/gate.py

@@ -32,6 +32,7 @@ class Gate(Exchange):
 
     _ft_has_futures: Dict = {
         "needs_trading_fees": True,
+        "tickers_have_bid_ask": False,
         "fee_cost_in_contracts": False,  # Set explicitly to false for clarity
         "order_props_in_contracts": ['amount', 'filled', 'remaining'],
         "stop_price_type_field": "price_type",