chore(deps): bump cbindgen in /packages/cedar_ffi/src

Bumps [cbindgen](https://github.com/mozilla/cbindgen) from 0.26.0 to 0.28.0.
- [Release notes](https://github.com/mozilla/cbindgen/releases)
- [Changelog](https://github.com/mozilla/cbindgen/blob/master/CHANGES)
- [Commits](mozilla/cbindgen@0.26.0...0.28.0)

---
updated-dependencies:
- dependency-name: cbindgen
  dependency-version: 0.28.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Author: dependabot[bot]