add custom renovate config

Signed-off-by: Martin Schurz <[email protected]>

renovate.json

@@ -1,6 +1,15 @@
 {
   "$schema": "https://docs.renovatebot.com/renovate-schema.json",
   "extends": [
-    "config:base"
+    "config:base",
+    ":gitSignOff"
+  ],
+  "dependencyDashboard": true,
+  "dependencyDashboardAutoclose": true,
+  "packageRules": [
+    {
+      "matchUpdateTypes": ["patch", "minor"],
+      "automerge": true
+    }
   ]
 }