app/overrides/spree/admin/stock_locations/_form/add_supplier.html.erb.deface
<!-- insert_bottom "[data-hook=admin_stock_locations_form_fields]" -->
<%# Remove extra div and change classes %>
<% if spree_current_user.admin? %>
<div class='form-group'>
<%= f.field_container :supplier do %>
<%= f.label :supplier_id, Spree.t(:supplier) %>
<%= f.collection_select(:supplier_id, Spree::Supplier.all, :id, :name, { :include_blank => 'None' }, { :class => 'select2' }) %>
<%= f.error_message_on :supplier %>
<% end %>
</div>
<% end %>