Remove use of tox-siblings role
Its functionality has been merged into the tox role, so is no longer
needed.
Depends-On: Id61ae52d48b28cfc2221cb556a1c1f7c6dfd60dd
Change-Id: Ia449c7c20405e3554f9b265a3ea102a6056f2713
Monty Taylor
6 years ago