systemd-analyze: allow --quiet for condition checks

I figure these messages are rather unnecessary, so let the user quiet
them with the existing --quiet flag if desired. Makes systemd-analyze
condition a little more ergonomic in scripts.

src/shared/condition.c

@@ -1206,8 +1206,6 @@ bool condition_test_list(
 
         int triggered = -1;
 
-        assert(!!logger == !!to_string);
-
         /* If the condition list is empty, then it is true */
         if (!first)
                 return true;