Bugfix/Django 4: ugettext_lazy was removed in favor of gettext_lazy

[mbi]

Description

Django >= 4 removed ugettext_lazy, which was deprecated years ago.

Checklist

• [x] I have read the contribution guide
• [ ] Code lint checked via inv lint
• [ ] changes file included (see docs)
• [ ] Usage documentation added in case of new features
• [ ] Tests added

[yakky]

@mbi Thanks for this! I'll merge as is while I fix the github actions