fix: compare timeout with <= instead of <

closes freqtrade#12590

Backtesting assumes round dates, so a timeout at "candle length" needs
to timeout at the hour - not after the hour.
otherwise the timeout becomes either double (60 instead of 30) -
or longer by one "timeframe detail" (31 instead of 30).

Author: xmatthias

freqtrade/strategy/interface.py

@@ -1718,7 +1718,7 @@ def ft_check_timed_out(self, trade: Trade, order: Order, current_time: datetime)
             timeout_unit = self.config.get("unfilledtimeout", {}).get("unit", "minutes")
             timeout_kwargs = {timeout_unit: -timeout}
             timeout_threshold = current_time + timedelta(**timeout_kwargs)
-            timedout = order.status == "open" and order.order_date_utc < timeout_threshold
+            timedout = order.status == "open" and order.order_date_utc <= timeout_threshold
             if timedout:
                 return True
         time_method = (