Fix type in test class name
Protect auth signing with a lock

The parts that manipulate the .auth_path aren't thread safe.
While we can possibly make this more granular, the entire
`before-auth` and `add_auth` calls are protected with a lock.
All of the existing auth signing code is CPU bound, so this
won't negatively impact performance.
Merge branch 'lock-auth' into develop

* lock-auth:
  Protect auth signing with a lock
  Fix type in test class name