Deduction validity checking

* fixes behaviour of related deduction checks on intervention checking

intervention/forms/modals/check.py

@@ -43,6 +43,7 @@ class CheckModalForm(BaseModalForm):
 
         """
         deductions = self.instance.deductions.all()
+        valid = True
         for deduction in deductions:
             checker = deduction.account.quality_check()
             for msg in checker.messages:
@@ -50,8 +51,8 @@ class CheckModalForm(BaseModalForm):
                     "checked_comps",
                     f"{deduction.account.identifier}: {msg}"
                 )
-            return checker.valid
-        return True
+            valid &= checker.valid
+        return valid
 
     def _are_comps_valid(self):
         """ Performs validity checks on all types of compensations