build(deps): Bump external/fmt from 01914f0 to f90090b

Bumps [external/fmt](https://github.com/fmtlib/fmt) from `01914f0` to `f90090b`.
- [Release notes](https://github.com/fmtlib/fmt/releases)
- [Commits](fmtlib/fmt@01914f0...f90090b)

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

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