Fix default gender
What does this MR do?
Changes the database so default gender is not NULL anymore but "other". This change is irrelevant to introduce in production as the registration process makes this sure anyway.
How confident are you it won't break things if deployed?
quite, just migration for tests
Links to related issues
- added a test, or explain why one is not needed/possible...
- no unrelated changes
- asked someone for a code review
- joined #foodsharing-beta channel at https://slackin.yunity.org
- added an entry to CHANGELOG.md (description, merge request link, username(s))