Fix trailing whitespace

Author: David Heinemeier Hansson

actioncable/lib/rails/generators/channel/channel_generator.rb

@@ -61,13 +61,13 @@ def create_channel_javascript_file
         end
 
         def import_channels_in_javascript_entrypoint
-          append_to_file "app/javascript/application.js", 
+          append_to_file "app/javascript/application.js",
             using_node? ? %(import "./channels"\n) : %(import "channels"\n)
         end
 
         def import_channel_in_javascript_entrypoint
           append_to_file "app/javascript/channels/index.js",
-            using_node? ? %(import "./#{file_name}_channel"\n) : %(import "channels/#{file_name}_channel"\n)          
+            using_node? ? %(import "./#{file_name}_channel"\n) : %(import "channels/#{file_name}_channel"\n)       
         end
 
         def install_javascript_dependencies