*: Switch consumers over to Django 5.2

Django 4.2 reached its End-of-Life on 7th April 2026 and Django 5.2 is
the new LTS (= Long Term Support) release which will be supported until
April 2028.

• Switch most ports that use www/py-django42 to www/py-django52.

• Where necessary, remove PORTSCOUT, which is no longer needed because an update to a newer version that no longer supports Django 4.2 should now be possible.

• Bump PORTREVISION due dependency change where necessary.

PR: 291707
Reviewed by: sunpoet (python)
Differential Revision: https://reviews.freebsd.org/D56966