adds gitfork information

renovate.json

@@ -3,5 +3,20 @@
     "extends": [
       "config:base", 
       ":disableDependencyDashboard"
-    ]
-}
\ No newline at end of file
+    ],
+    "packageRules": [
+      {
+        "groupName": "git fork",
+        "matchManagers": [
+          "gitfork"
+        ],
+        "automerge": true,
+        "automergeType": "pr",
+        "platformAutomerge": true,
+        "rebaseWhen": "auto"
+      }
+    ],
+    "gitfork": {
+      "repository": "https://git.code.tecnalia.com/smartdatalab/public/applications/renovate-sample-base.git"
+    }
+  }
\ No newline at end of file