build(deps): Bump external/Phi from bb0409a to 5cf1bf1

Bumps [external/Phi](https://github.com/AMS21/Phi) from `bb0409a` to `5cf1bf1`.
- [Commits](AMS21/Phi@bb0409a...5cf1bf1)

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

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