Bump @octokit/rest from 18.12.0 to 20.1.0

Bumps [@octokit/rest](https://github.com/octokit/rest.js) from 18.12.0 to 20.1.0.
- [Release notes](https://github.com/octokit/rest.js/releases)
- [Commits](octokit/rest.js@v18.12.0...v20.1.0)

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

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