Neither bundle supports recent Symfony versions. Their features are
reimplemented in the application, keeping the existing behavior:

- User and Usergroup no longer extend the bundles' models: the mapped
  fields are moved to UserAccountTrait and UserProfileTrait with an
  identical mapping (no schema change), validation rules included.
- App\Security\User: user manager, provider (username or email),
  programmatic login, password reset mailer, token generator. A
  Doctrine listener keeps canonical fields and password hash up to date
  on every persist, like FOSUserBundle did.
- Login, profile, password change/reset and registration controllers
  keep the fos_user_* route names, paths and form names, so templates
  are unchanged. FOS templates are served from the @FOSUser namespace
  and FOS translations are kept with a lower priority.
- The user and group admins keep their "sonata.user.admin.*" codes, so
  the ROLE_SONATA_USER_ADMIN_* roles stored in database still apply.
  The roles widget is copied from SonataUserBundle.
- The SonataUserBundle admin login pages are dropped: /admin/login and
  /admin/resetting/request redirect to the front pages.

Add UserAccountTest covering login, password reset and change, and
user creation in the admin; it passes on both the old and new code.