Update engine_cart stanza

Gemfile

@@ -13,8 +13,8 @@ gemspec
 # To use a debugger
 # gem 'byebug', group: [:development, :test]
 # BEGIN ENGINE_CART BLOCK
-# engine_cart: 1.2.0
-# engine_cart stanza: 0.10.0
+# engine_cart: 2.6.0
+# engine_cart stanza: 2.5.0
 # the below comes from engine_cart, a gem used to test this Rails engine gem in the context of a Rails app.
 file = File.expand_path('Gemfile', ENV['ENGINE_CART_DESTINATION'] || ENV['RAILS_ROOT'] || File.expand_path('.internal_test_app', File.dirname(__FILE__)))
 if File.exist?(file)
@@ -34,17 +34,16 @@ else
     else
       gem 'rails', ENV['RAILS_VERSION']
     end
-  end
 
-  case ENV['RAILS_VERSION']
-  when /^5.[12]/
-    gem 'sass-rails', '~> 5.0'
-  when /^4.2/
-    gem 'responders', '~> 2.0'
-    gem 'sass-rails', '>= 5.0'
-    gem 'coffee-rails', '~> 4.1.0'
-  when /^4.[01]/
-    gem 'sass-rails', '< 5.0'
+    case ENV['RAILS_VERSION']
+    when /^6.0/
+      gem 'sass-rails', '>= 6'
+      gem 'webpacker', '~> 4.0'
+    when /^5.[12]/
+      gem 'sass-rails', '~> 5.0'
+      gem 'sprockets', '~> 3.7'
+      gem 'thor', '~> 0.20'
+    end
   end
 end
 # END ENGINE_CART BLOCK