Improve dev experience

[Tymmmy]

Context

We have made great improvements on developer experience by having automatic [email protected] user already in place, when a new local environment is installed. The [email protected] user already has a USD account, and payment pointer as well. The recent rafiki admin changes have made it more difficult to access admin side, and add new assets, when locally docker is cleared. We should continue dev experience improvement, by adding an automatic admin user for [email protected], this way the user can already log in to rafiki admin, and add new assets easily.

Todos

• [x] Add [email protected] user into the rafiki admin users automaticaly when doing a local environment install of test network
• [x] If possible already set up password for admin user to be 123456