[ffigen] Bump coverallsapp/github-action from 1.1.3 to 1.2.4 (#523)

Bumps [coverallsapp/github-action](https://github.com/coverallsapp/github-action) from 1.1.3 to 1.2.4.
- [Release notes](https://github.com/coverallsapp/github-action/releases)
- [Commits](https://github.com/coverallsapp/github-action/compare/9ba913c152ae4be1327bfb9085dc806cedb44057...50c33ad324a9902697adbf2f92c22cf5023eacf1)

---
updated-dependencies:
- dependency-name: coverallsapp/github-action
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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