Add a section on how to configure user/password for unity-accelerator dashboard

[FilipSivak]

Hi!

First of all thanks for great work! It puzzled me what was the default account/password for dashboard until I've figured there is non. Having short info on how to actually go into container and change it could be useful.

Thanks!

[shiena]

Thank you.
You can also use environment variables for the username and password.
How about these methods?

modify accelerator.env

USER=foo
PASSWORD=bar

or modify docker-compose.yml

accelerator:
  environment:
    - USER=foo
    - PASSWORD=bar

or alternative modify docker-compose.yml

# on shell
USER=foo
PASSWORD=bar

and

accelerator:
  environment:
    - USER
    - PASSWORD

see also

• https://docs.unity3d.com/Manual/UnityAccelerator.html#docker
• https://docs.docker.com/compose/environment-variables/

[FilipSivak]

@shiena Yes, you are correct. I guess I should have read Unity documentation on containers more thoroughly. However, I was thrown off by the dashboard having no configured account by default. I think including the "admin/admin" account in accelerator.env to have the container work out of the box might help others with rapid adoption / quick hacking.