Remove trailing whitespace who offended rubocop

Author: lucke84

app/helpers/react_on_rails_helper.rb

@@ -338,7 +338,7 @@ def initialize_redux_stores
   # second parameter passed to both component and store generator functions.
   def rails_context(server_side:)
     @rails_context ||= begin
-      # Using Addressable instead of standard URI to better deal with 
+      # Using Addressable instead of standard URI to better deal with
       # non-ASCII characters (see https://github.com/shakacode/react_on_rails/pull/405)
       uri = Addressable::URI.parse(request.original_url)
       # uri = Addressable::URI.parse("http://foo.com:3000/posts?id=30&limit=5#time=1305298413")