fix(deps): bump @octokit/rest from 16.28.7 to 18.12.0

Bumps [@octokit/rest](https://github.com/octokit/rest.js) from 16.28.7 to 18.12.0.
- [Release notes](https://github.com/octokit/rest.js/releases)
- [Commits](octokit/rest.js@v16.28.7...v18.12.0)

---
updated-dependencies:
- dependency-name: "@octokit/rest"
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]