Correctly handle a failure to create a new Geo node

ee/app/controllers/admin/geo_nodes_controller.rb

@@ -18,6 +18,9 @@ class Admin::GeoNodesController < Admin::ApplicationController
       redirect_to admin_geo_nodes_path, notice: 'Node was successfully created.'
     else
       @nodes = GeoNode.all
+      @node = GeoNode.new(geo_node_params)
+      flash.now[:alert] = 'Failed to create new node'
+
       render :index
     end
   end