Add git signoff

Signed-off-by: Andy Scherzinger <info@andy-scherzinger.de>

renovate.json5

@@ -1,7 +1,8 @@
 {
   "$schema": "https://docs.renovatebot.com/renovate-schema.json",
   "extends": [
-    "config:recommended"
+    "config:recommended",
+    ":gitSignOff"
   ],
   "timezone": "Europe/Berlin",
   "labels": [