reports: Balance.clean_copy() creates new Balance with given tolerance.

conservancy_beancount/reports/core.py

@@ -174,8 +174,8 @@ class Balance(Mapping[str, data.Amount]):
         if tolerance is None:
             tolerance = self.tolerance
         return type(self)(
-            amount for amount in self.values()
-            if abs(amount.number) >= tolerance
+            (amount for amount in self.values() if abs(amount.number) >= tolerance),
+            tolerance,
         )
 
     @staticmethod