Bump mods/default from 2f3622d to 859bb6f

Bumps [mods/default](https://github.com/minetest-game/default) from `2f3622d` to `859bb6f`.
- [Commits](minetest-game/default@2f3622d...859bb6f)

---
updated-dependencies:
- dependency-name: mods/default
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>