chore(deps): update dependency @octokit/rest to v21

Author: renovate[bot]

package.json

@@ -27,7 +27,7 @@
     "@intlify/core-base": "next",
     "@kazupon/eslint-config": "^0.18.0",
     "@kazupon/lerna-changelog": "^4.3.0",
-    "@octokit/rest": "^20.0.0",
+    "@octokit/rest": "^21.0.0",
     "@rollup/plugin-alias": "^3.1.5",
     "@rollup/plugin-commonjs": "^19.0.0",
     "@rollup/plugin-node-resolve": "^13.0.0",