Update jquery-ui-rails (6.0.1)

backend/app/assets/javascripts/spree/backend.js

@@ -5,9 +5,9 @@
 //= require jquery.cookie
 //= require jquery.jstree/jquery.jstree
 //= require jquery_ujs
-//= require jquery-ui/datepicker
-//= require jquery-ui/sortable
-//= require jquery-ui/autocomplete
+//= require jquery-ui/widgets/datepicker
+//= require jquery-ui/widgets/sortable
+//= require jquery-ui/widgets/autocomplete
 //= require select2
 //= require underscore-min.js
 //= require velocity

backend/config/initializers/assets.rb

@@ -1 +1 @@
-Rails.application.config.assets.precompile += %w( jquery-ui/* admin/* credit_cards/credit_card.gif )
+Rails.application.config.assets.precompile += %w( admin/* credit_cards/credit_card.gif )

backend/spree_backend.gemspec

@@ -24,6 +24,6 @@ Gem::Specification.new do |s|
 
   s.add_dependency 'bootstrap-sass',  '~> 3.3'
   s.add_dependency 'jquery-rails',    '~> 4.1'
-  s.add_dependency 'jquery-ui-rails', '~> 5.0'
+  s.add_dependency 'jquery-ui-rails', '~> 6.0.1'
   s.add_dependency 'select2-rails',   '3.5.9.1' # 3.5.9.2 breaks several specs
 end