SYMFONY__ENV__DOMAIN_NAME set, but confirmation mail from localhost

Hi,

Just getting Wallabag running for the first time, but having issues getting my domain to come through on the confirmation email:

```
Hello itsthejb!

To finish activating your account - please visit http://0.0.0.0:5841/register/confirm/FlEgET0IMMZT6BxCGfJuMjEW4RG91wNmL02YB4rFbt4

This link can only be used once to validate your account.

Regards,
the Team.
```

My `docker-compose.yml`:

```
wallabag:
container_name: wallabag
image: wallabag/wallabag
environment:
- SYMFONY__ENV__DOMAIN_NAME=https://wallabag.myhost.org
- MYSQL_ROOT_PASSWORD=wallaroot
- SYMFONY__ENV__DATABASE_DRIVER=pdo_mysql
- SYMFONY__ENV__DATABASE_HOST=db
- SYMFONY__ENV__DATABASE_PORT=3306
- SYMFONY__ENV__DATABASE_NAME=wallabag
- SYMFONY__ENV__DATABASE_USER=wallabag
- SYMFONY__ENV__DATABASE_PASSWORD=wallapass
- SYMFONY__ENV__MAILER_HOST=192.168.178.22
- SYMFONY__ENV__MAILER_USER=email@myemail.com
- SYMFONY__ENV__MAILER_PASSWORD=emailpassword
- SYMFONY__ENV__FROM_EMAIL=wallabag@myhost.org
- SYMFONY__ENV__DATABASE_CHARSET=utf8mb4
ports:
- "5841:80"
volumes:
- /docker/appdata/wallabag/images:/var/www/wallabag/web/assets/images
```

It seems from other issues that only `SYMFONY__ENV__DOMAIN_NAME` is required, but no luck. What am I getting wrong?

Thanks