Bump external/elfio from eb68829 to 4bc17b6

Bumps [external/elfio](https://github.com/serge1/ELFIO) from `eb68829` to `4bc17b6`.
- [Release notes](https://github.com/serge1/ELFIO/releases)
- [Commits](serge1/ELFIO@eb68829...4bc17b6)

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

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