title: Stub ActiveJob with Rspec
body: <p>I have an active job <code>SubscribeUserToMailingListJob</code> that updates my Mailchimp list everytime a user is created using an after_commit callback. </p>
  
  <p>When I run my test suite, these updates are fired, causing a lot of "cannot find Model with ID=1234" errors to be posted to Rollbar. I would like to stub out <code>SubscribeUserToMailingListJob</code> when creating fake users for testing, without affecting the test for the job itself.</p>