Bump third_party/open-source-pdks from `fd509b9` to `0516eff`

Bumps [third_party/open-source-pdks](https://github.com/google/open-source-pdks) from `fd509b9` to `0516eff`.
- [Release notes](https://github.com/google/open-source-pdks/releases)
- [Commits](https://github.com/google/open-source-pdks/compare/fd509b924cb902dd0650d04889a95072040144ee...0516effa229623ee8ecdb44df79f519af25d38b8)

---
updated-dependencies:
- dependency-name: third_party/open-source-pdks
  dependency-type: direct:production
...

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