Bump ouroboros from 0.15.3 to 0.15.4 in /src/rust (#7557)

Bumps [ouroboros](https://github.com/joshua-maros/ouroboros) from 0.15.3 to 0.15.4.
- [Release notes](https://github.com/joshua-maros/ouroboros/releases)
- [Commits](https://github.com/joshua-maros/ouroboros/commits)

---
updated-dependencies:
- dependency-name: ouroboros
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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