Add renovate.json

Author: renovate[bot]

.github/renovate.json

@@ -0,0 +1,6 @@
+{
+  "$schema": "https://docs.renovatebot.com/renovate-schema.json",
+  "extends": [
+    "github>WyriHaximus/renovate-config:github-action"
+  ]
+}