This patch is only for python3-django_2.2.28.
The URL validator didn't detect invalid IPv6 addresses, treating them
as correct ones, making a testcase fail. (Also, according to the comment,
it could also crash in some cases, though I haven't encountered that)
This backported patch mitigates this behavior.
Signed-off-by: Gyorgy Sarvari <skandigraun@gmail.com>