Update offline-github-changelog to version 2.4.0

Author: depfu[bot]

package.json

@@ -18,7 +18,7 @@
     "eslint-plugin-standard": "^5.0.0",
     "mocha": "^8.2.1",
     "nyc": "^15.0.0",
-    "offline-github-changelog": "^1.7.0",
+    "offline-github-changelog": "^2.4.0",
     "prettier": "~2.4.0",
     "unexpected": "^12.0.0",
     "unexpected-documentation-site-generator": "^6.0.0",