Bump matprep_artifacts from 6c272f3 to c7e99e5

Bumps [matprep_artifacts](https://github.com/a-hurst/matprep_artifacts) from `6c272f3` to `c7e99e5`.
- [Release notes](https://github.com/a-hurst/matprep_artifacts/releases)
- [Commits](a-hurst/matprep_artifacts@6c272f3...c7e99e5)

---
updated-dependencies:
- dependency-name: matprep_artifacts
  dependency-version: c7e99e5329afc505ba071f856242f47373fe87a7
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]