Bump hexo-generator-feed from 3.0.0 to 4.0.0

Bumps [hexo-generator-feed](https://github.com/hexojs/hexo-generator-feed) from 3.0.0 to 4.0.0.
- [Release notes](https://github.com/hexojs/hexo-generator-feed/releases)
- [Commits](hexojs/hexo-generator-feed@3.0.0...v4.0.0)

---
updated-dependencies:
- dependency-name: hexo-generator-feed
  dependency-version: 4.0.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

package-lock.json

@@ -18,7 +18,7 @@
     "hexo-deployer-git": "^3.0.0",
     "hexo-generator-archive": "^2.0.0",
     "hexo-generator-category": "^2.0.0",
-    "hexo-generator-feed": "^3.0.0",
+    "hexo-generator-feed": "^4.0.0",
     "hexo-generator-index": "^3.0.0",
     "hexo-generator-sitemap": "^3.0.1",
     "hexo-generator-tag": "^2.0.0",