How to make stopwords path text file work with words that have single quotes

I have the following stopwords filter:


 "english_stop": {
          "type": "stop",
          "stopwords_path": "/usr/local/etc/elasticsearch/stopwords.txt",
          "updateable": true
}

These are the words in my stopwords.txt file:

forbe
and
fox
rail
these
it's

All the words return 0 results as expected except for "it's" which has a single quote/apostrophe in it.

I've tried escaping the single quote using html code and/or unicode but no luck.

Any help would be appreciated.