**Backport:** https://codeberg.org/forgejo/forgejo/pulls/7395
- Add `binding:"In(...)"` to the `default_merge_style` and `default_update_style` fields to only accept recognized merge and update styles.
- Resolvesforgejo/forgejo#7389
- Added integration test for the API (`binding` works in the exact same way for the API and web routes).
Co-authored-by: Gusted <postmaster@gusted.xyz>
Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/7401
Reviewed-by: Earl Warren <earl-warren@noreply.codeberg.org>
Co-authored-by: forgejo-backport-action <forgejo-backport-action@noreply.codeberg.org>
Co-committed-by: forgejo-backport-action <forgejo-backport-action@noreply.codeberg.org>