Fix a link with trailing slash that does not work [ci-skip]

Author: kamipo

guides/source/upgrading_ruby_on_rails.md

@@ -2483,7 +2483,7 @@ being used, you can update your form to use the `PUT` method instead:
 <%= form_for [ :update_name, @user ], method: :put do |f| %>
 ```
 
-For more on PATCH and why this change was made, see [this post](https://rubyonrails.org/2012/2/26/edge-rails-patch-is-the-new-primary-http-method-for-updates/)
+For more on PATCH and why this change was made, see [this post](https://rubyonrails.org/2012/2/26/edge-rails-patch-is-the-new-primary-http-method-for-updates)
 on the Rails blog.
 
 #### A note about media types