In Odoo, ldap, qrcode and vobject python modules are set as required in
odoo/setup.py. On the other hand, they are only recommendend in the
Debian package.
As a consequence, it was difficult to run some Odoo modules that
required one of them.
The Odoo Debian package was adapted in master where they were added as
dependencies in odoo/odoo@2ff49c5fcb .
With this commit, they are installed in the Docker images.
This is a part of the fix of odoo/odoo#27752.
locale settings does not need to re-genreate c.utf-8 as it's already
included in Debian Stretch. Also LANG is enough to define the locale
needed by Odoo. Finaly, apt-get does not really need to be explicitly
set in non interactive mode. apt-get is able to do the right thing.
Thanks @tianon
