chore(renovate): add renovate.json with detected managers (#1)

Author: thibautvanderhaegen

renovate.json

@@ -0,0 +1,5 @@
+{
+  "$schema": "https://docs.renovatebot.com/renovate-schema.json",
+  "extends": ["local>Xelians/renovate-config"],
+  "enabledManagers": ["gradle", "gradle-wrapper"]
+}