Bump next from 9.3.6 to 9.4.0

Bumps [next](https://github.com/zeit/next.js) from 9.3.6 to 9.4.0.
- [Release notes](https://github.com/zeit/next.js/releases)
- [Commits](https://github.com/zeit/next.js/compare/v9.3.6...v9.4.0)

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

package.json

@@ -19,7 +19,7 @@
   },
   "dependencies": {
     "fathom-client": "^2.0.3",
-    "next": "^9.3.6",
+    "next": "^9.4.0",
     "next-seo": "^4.4.0",
     "react": "^16.13.1",
     "react-clipboard.js": "^2.0.16",