stubby: restart on trigger interfaces

Force restart stubby if any of the trigger interfaces goes up or down.
Avoids DoT DNS lookup timeouts when default route changes, in case of multiple
upstream interfaces.

Signed-off-by: Aleksandr V. Piskunov <aleksandr.v.piskunov@gmail.com>

net/stubby/files/stubby.init

@@ -270,7 +270,7 @@ service_triggers()
 
     for trigger_item in $trigger
     do
-        procd_add_interface_trigger "interface.*.up" "$trigger_item" "$stubby_init" start
+        procd_add_interface_trigger "interface.*" "$trigger_item" "$stubby_init" restart
     done
 
     procd_add_reload_trigger "stubby"