feat: permissions (#168)

- Load `app-permissions` from schema exported by `@octokit/openapi`
- Update documentation in README.md
- Implement the `permissions_*` inputs in the action code

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Co-authored-by: Parker Brown <17183625+parkerbxyz@users.noreply.github.com>

package.json

@@ -16,9 +16,10 @@
     "@octokit/auth-app": "^7.1.5",
     "@octokit/request": "^9.2.2",
     "p-retry": "^6.2.1",
-    "undici": "^7.4.0"
+    "undici": "^7.5.0"
   },
   "devDependencies": {
+    "@octokit/openapi": "^18.0.0",
     "@sinonjs/fake-timers": "^14.0.0",
     "ava": "^6.2.0",
     "c8": "^10.1.3",