Configure JWT gateway authentication

[abikouo]

This draft pull request addresses concerns from https://issues.redhat.com/browse/AAP-47177.

• Regarding the authentication, we can rely on the Gateway authentication JWT token; the only thing we have to do is to add the following configuration in the settings

REST_FRAMEWORK = {
    "DEFAULT_AUTHENTICATION_CLASSES": [
        "pattern_service.authentication.PatternServiceJWTAuthentication",
    ],
    "DEFAULT_PERMISSION_CLASSES": [
        "ansible_base.rbac.api.permissions.AnsibleBaseObjectPermissions",
    ],
}

Some ANSIBLE_BASE* variables also need to be defined
However, we still need to define a User model in our app, even if this is not used to store user information. As the django-ansible-base is not well-documented, this may require further investigation to determine if it can be removed.

• Regarding the created_by and modified_by, these fields cannot be updated as they are defined now with the user's Ansible ID from the Gateway because they are currently defined as ForeignKey. This prototype adds a new field created_by_ansible_id which will store the user's Ansible ID. Another solution is to update these fields