application: Print positive delta when changing verbosity

Since we already take into account if it's increasing or decreasing
we should make the amount (Increased/Decreased by N) positive.

src/calls-application.c

@@ -517,7 +517,7 @@ calls_application_command_line (GApplication            *application,
     if (delta != 0)
       g_print ("%s verbosity by %d to %u\n",
                delta > 0 ? "Increased" : "Decreased",
-               delta,
+               delta < 0 ? -1 * delta : delta,
                level);
   }