fix(deps): update dependency octokit-plugin-create-pull-request to v4 (#25)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

package-lock.json

@@ -19,7 +19,7 @@
   "license": "ISC",
   "dependencies": {
     "@octoherd/cli": "^3.3.4",
-    "octokit-plugin-create-pull-request": "^3.9.3",
+    "octokit-plugin-create-pull-request": "^4.0.0",
     "prettier": "^2.3.2",
     "yaml": "^2.0.0-6"
   },