Bump rustix from 0.38.17 to 0.38.19 in /miri-script

Bumps [rustix](https://github.com/bytecodealliance/rustix) from 0.38.17 to 0.38.19.
- [Release notes](https://github.com/bytecodealliance/rustix/releases)
- [Commits](bytecodealliance/rustix@v0.38.17...v0.38.19)

---
updated-dependencies:
- dependency-name: rustix
  dependency-type: indirect
...

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Author: dependabot[bot]