Bump steno from c6ea85c to 578498b

Bumps [steno](https://github.com/oxidecomputer/steno) from `c6ea85c` to `578498b`.
- [Release notes](https://github.com/oxidecomputer/steno/releases)
- [Commits](oxidecomputer/steno@c6ea85c...578498b)

---
updated-dependencies:
- dependency-name: steno
  dependency-type: direct:production
...

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