Increase link checker timeout from 10s to 20s

So slow responding sites have a chance to not be marked as dead.

Author: sverhoeven

{{cookiecutter.project_name}}/.mlc-config.json

@@ -12,5 +12,6 @@
         }
     ],
     "replacementPatterns": [
-    ]
+    ],
+    "timeout": "20s"
 }