Wrap cleanup in try/finally handler

If a database has errors, the database cleanups would fail, causing
cleanup to be incomplete.

closes #7364

freqtrade/freqtradebot.py

@@ -142,12 +142,15 @@ class FreqtradeBot(LoggingMixin):
         :return: None
         """
         logger.info('Cleaning up modules ...')
-
+        try:
+            # Wrap db activities in shutdown to avoid problems if database is gone,
+            # and raises further exceptions.
             if self.config['cancel_open_orders_on_exit']:
                 self.cancel_all_open_orders()
 
             self.check_for_open_trades()
 
+        finally:
             self.strategy.ft_bot_cleanup()
 
             self.rpc.cleanup()