app/views/rails_admin/main/edit.html.erb
<%= rails_admin_form_for @object, url: edit_path(@abstract_model, @object.id), as: @abstract_model.param_key, html: { method: "put", multipart: true, class: "main", data: { title: @page_name } } do |form| %>
<%= form.generate action: :update %>
<% end %>