ember twitter bootstrap ember-sass ember-modal-dialog extra arrows in select tag

I have an ember project with twitter bootstrap 4. After adding ember-sass my select tags now show up like the following:

The arrows to the far right, are the problem.

Any insight on how to remove the arrows to the far right would be greatly appreciated.

I also added ember-modal-dialog, I do not think this caused any issue but not sure, so I will just mention it.