misc: use application/javascript for menu.json served as jsonp (#14685)

hobo/views.py

@@ -133,15 +133,17 @@ def health_json(request):
 
 @admin_required
 def menu_json(request):
-    response = HttpResponse(content_type='application/json')
     label = _('System')
     json_str = json.dumps([{'label': force_text(label),
         'slug': 'system',
         'url': request.build_absolute_uri(reverse('home'))
         }])
+    content_type = 'application/json'
     for variable in ('jsonpCallback', 'callback'):
         if variable in request.GET:
             json_str = '%s(%s);' % (request.GET[variable], json_str)
+            content_type = 'application/javascript'
             break
+    response = HttpResponse(content_type=content_type)
     response.write(json_str)
     return response