package/python-django: security bump to version 3.0.12

package/python-django: security bump to version 3.0.12

Fixes the following security issues:

CVE-2021-3281: Potential directory-traversal via archive.extract()

The django.utils.archive.extract() function, used by startapp --template and
startproject --template, allowed directory-traversal via an archive with
absolute paths or relative paths with dot segments.

For details, see the advisory:
https://www.djangoproject.com/weblog/2021/feb/01/security-releases/

Additionally, 3.0.11 fixed a regression:
https://docs.djangoproject.com/en/3.1/releases/3.0.11/

Update indentation in hash file (two spaces).

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>