IMPORTANT NOTE please notice that the development environment does not use the inventory or startup scripts from the production container. It uses a docker-compose workflow, as a starting point you can see: https://github.com/ansible/awx/blob/devel/Makefile#L556-L557
There is a pinned item at the top of this Google group that is my intro presentation to the AWX development environment that I gave at Fest a month or so ago where I walk through this all step-by-step, though if you follow along with the CONTRIBUTING.md you should get there also.