[Core] Authenticate the user before saving it

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | specs yes
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

User was not authenticated, so the listener was not linking User and Order because it was using security context.