package/python-django: bump to 6.0

package/python-django: bump to 6.0

Release Notes: https://docs.djangoproject.com/en/6.0/releases/6.0/

A few changes in the license files and an actual (sub)-license update:

* django/contrib/gis/measure.py -> formatting change
* django/contrib/admin/static/admin/img -> svg files got uupdated and
  the new ones are licensed under CC-BY-4.0; separate LICENSE file got
  removed, License is now mentioned in the readme
* django/utils/archive.py -> File got updated, license (which is only
  the header) did not change.

Remove the comment about django site having an inconvenient download
URL. We download pretty much all python package from pypi.org, so doing
that for django shouldn't need a separate comment.

Signed-off-by: Marcus Hoffmann <buildroot@bubu1.eu>
Signed-off-by: Julien Olivain <ju.o@free.fr>