feat: upgrade @octokit/rest from 19.0.5 to 21.0.2

Snyk has created this PR to upgrade @octokit/rest from 19.0.5 to 21.0.2.

See this package in npm:
@octokit/rest

See this project in Snyk:
https://app.snyk.io/org/cachiman/project/70b0c924-5766-4f16-897a-065d03b31bf1?utm_source=github&utm_medium=referral&page=upgrade-pr

packages/owlbot-bootstrapper/common-container/package.json

@@ -30,7 +30,7 @@
     "@google-cloud/secret-manager": "^4.1.2",
     "@google-cloud/storage": "^6.5.2",
     "@octokit/auth-app": "^4.0.5",
-    "@octokit/rest": "^19.0.4",
+    "@octokit/rest": "^21.0.2",
     "@types/yargs": "^17.0.12",
     "gaxios": "^5.0.1",
     "gcf-utils": "^14.0.1",