Extend grafana-renovate-config base preset

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: korniltsev-grafanista

renovate.json

@@ -0,0 +1,7 @@
+{
+  "$schema": "https://docs.renovatebot.com/renovate-schema.json",
+  "extends": [
+    "github>grafana/grafana-renovate-config//presets/base",
+    "security:only-security-updates"
+  ]
+}