Bump mocpy from 0.12.1 to 0.12.3

Bumps [mocpy](https://github.com/cds-astro/mocpy) from 0.12.1 to 0.12.3.
- [Release notes](https://github.com/cds-astro/mocpy/releases)
- [Changelog](https://github.com/cds-astro/mocpy/blob/master/CHANGELOG.md)
- [Commits](cds-astro/mocpy@v0.12.1...v0.12.3)

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

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