build(deps): bump external/minidx9 from 7751cf7 to f481ecb (#1633)

Bumps [external/minidx9](https://github.com/hrydgard/minidx9) from `7751cf7` to `f481ecb`.
- [Commits](hrydgard/minidx9@7751cf7...f481ecb)

---
updated-dependencies:
- dependency-name: external/minidx9
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>