before this commit, after running an older version,
 lets say odoo 14 and trying to access 16 in the
 same browser return traceback without redirecting
  to db selector page

 and this happens due to the missing env in request,
 which returns as None.

 after this commit, no traceback wont be shown and
 will open the db selector page

closes odoo/odoo#116351

Signed-off-by: Julien Castiaux (juc) <juc@odoo.com>