Is your feature request related to a problem? Please describe.
Currently there is no way to set a custom Redis username

Describe the solution you'd like
Add an environment variable for configuring the Redis username

Describe alternatives you've considered
Add an environment variable for setting a Redis Connection URL

Additional context
I have a setup where multiple applications use the same DragonflyDB (Redis compatible DB) instance. Because of that I have one users per application. Each user has is own database only they are allowed to select.