Move config json validation to after strategy loading

Otherwise attributes are mandatory in configuration
while they could be set in the strategy

freqtrade/optimize/backtesting.py

@@ -13,7 +13,8 @@ from pandas import DataFrame
 from tabulate import tabulate
 
 from freqtrade import OperationalException
-from freqtrade.configuration import TimeRange, remove_credentials
+from freqtrade.configuration import (TimeRange, remove_credentials,
+                                     validate_config_consistency)
 from freqtrade.data import history
 from freqtrade.data.dataprovider import DataProvider
 from freqtrade.exchange import timeframe_to_minutes, timeframe_to_seconds
@@ -75,10 +76,12 @@ class Backtesting:
                 stratconf = deepcopy(self.config)
                 stratconf['strategy'] = strat
                 self.strategylist.append(StrategyResolver(stratconf).strategy)
+                validate_config_consistency(stratconf)
 
         else:
             # No strategy list specified, only one strategy
             self.strategylist.append(StrategyResolver(self.config).strategy)
+            validate_config_consistency(self.config)
 
         if "ticker_interval" not in self.config:
             raise OperationalException("Ticker-interval needs to be set in either configuration "

freqtrade/optimize/edge_cli.py

@@ -9,7 +9,8 @@ from typing import Any, Dict
 from tabulate import tabulate
 
 from freqtrade import constants
-from freqtrade.configuration import TimeRange, remove_credentials
+from freqtrade.configuration import (TimeRange, remove_credentials,
+                                     validate_config_consistency)
 from freqtrade.edge import Edge
 from freqtrade.exchange import Exchange
 from freqtrade.resolvers import StrategyResolver
@@ -35,6 +36,8 @@ class EdgeCli:
         self.exchange = Exchange(self.config)
         self.strategy = StrategyResolver(self.config).strategy
 
+        validate_config_consistency(self.config)
+
         self.edge = Edge(config, self.exchange, self.strategy)
         # Set refresh_pairs to false for edge-cli (it must be true for edge)
         self.edge._refresh_pairs = False