Bump @octokit/rest from 20.1.1 to 21.0.1

Bumps [@octokit/rest](https://github.com/octokit/rest.js) from 20.1.1 to 21.0.1.
- [Release notes](https://github.com/octokit/rest.js/releases)
- [Commits](octokit/rest.js@v20.1.1...v21.0.1)

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

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

package.json

@@ -15,7 +15,7 @@
   },
   "dependencies": {
     "@koa/router": "^12.0.1",
-    "@octokit/rest": "^20.1.1",
+    "@octokit/rest": "^21.0.1",
     "escape-goat": "^3.0.0",
     "github-username-regex": "^1.0.0",
     "handlebars": "^4.7.8",