Implement bearer Token RBAC from Keycloak

[FlatBallFlyer]

Implement an internal create_token function with the same signature as py_utils create_token(). It should validate a JWT - raising an exception on failure, and populate the user_id and roles values from jwt claims. The implementation should be provider independent, we will perform end-to-end testing with KeyCloak

This will require an update to py_utils Config to include JWT Validation Key.

Make sure to update README with CURL commands to use static non-expiring JWT's.
Make sure to update the StepCI testing

Implement the RBAC logic that allows any valid token holder to access the render endpoints, and get configurations. Only users with an admin role should be able to process configurations.