Bump once_cell from 1.20.3 to 1.21.3 in /src/_bcrypt

Bumps [once_cell](https://github.com/matklad/once_cell) from 1.20.3 to 1.21.3.
- [Changelog](https://github.com/matklad/once_cell/blob/master/CHANGELOG.md)
- [Commits](matklad/once_cell@v1.20.3...v1.21.3)

---
updated-dependencies:
- dependency-name: once_cell
  dependency-type: indirect
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]