fix(manager): systems_affected columns should never be NULL when appl…

…ying filters

...and for some reason postgresql executes the query faster

RHINENG-5256

manager/filters.py

@@ -671,9 +671,9 @@ def _filter_cve_by_affecting_host_type(query, args, kwargs):
         expr = None
         for arg in affecting:
             if arg == HostType.RPMDNF:
-                expr |= fn.COALESCE(count_subquery.c.systems_affected_rpmdnf_, 0) != 0
+                expr |= count_subquery.c.systems_affected_rpmdnf_ != 0
             elif arg == HostType.EDGE:
-                expr |= fn.COALESCE(count_subquery.c.systems_affected_edge_, 0) != 0
+                expr |= count_subquery.c.systems_affected_edge_ != 0
             elif arg == HostType.NONE:
                 expr |= (fn.COALESCE(count_subquery.c.systems_affected_rpmdnf_, 0) + fn.COALESCE(count_subquery.c.systems_affected_edge_, 0)) == 0
         if expr: