Interface loading icon usage change all fa-refresh to fa-spinner

In the design of https://gitlab.com/gitlab-org/gitlab-ce/issues/22071 the spinner is used as a loading icon animation. This is better than using fa-refresh as that is used else where in the application for something that is "retried" : https://gitlab.com/gitlab-org/gitlab-ce/issues/21192

One of the instances where the fa-refresh is currently used is in the text body popup loading animation:

This should be changed to fa-spinner

also we should scour the codebase for similar loading animations that use the fa-refresh and change those to fa-spinner