fix: account for htmx issues in mobile safari with select fields

templates/booking/create/step_1.html.twig

@@ -1,5 +1,7 @@
 {% extends 'layout_booking.html.twig' %}
 
+{% set htmx_change_trigger = 'change delay:300ms' %}
+
 {% macro stepFormField(form) %}
     <div class="grid grid-cols-3 pb-2">
         <div class="col-span-2 pr-2">
@@ -15,7 +17,7 @@
                 'attr': {
                     'hx-post': path('app_booking_create_step_1_refresh'),
                     'hx-swap': 'none',
-                    'hx-trigger': 'change delay:300ms',
+                    'hx-trigger': htmx_change_trigger,
                 }
             }) }}
         </div>