message: fix csrf error on import_dashboards
diff: <title>Import the dashboards.</title>
  <h1>Import the dashboards.</h1>
  <form method=post enctype=multipart/form-data>
  + <input
  + type="hidden"
  + name="csrf_token"
  + id="csrf_token"
  + value="{{ csrf_token() if csrf_token else '' }}"
  + >
  <p><input type=file name=file>
  <input type=submit value=Upload>
  </p>
  