Fix bug when modifying an order with an address in a country with a state

src/pretix/static/pretixcontrol/js/ui/main.js

@@ -343,7 +343,7 @@ var form_handlers = function (el) {
     $("select[name$=state]:not([data-static])").each(function () {
         var dependent = $(this),
             counter = 0,
-            dependency = $(this).closest("form").find('select[name$=country]'),
+            dependency = $(this).closest(".panel-body, form").find('select[name$=country]'),
             update = function (ev) {
                 counter++;
                 var curCounter = counter;