Add screenshot

README.md

@@ -8,6 +8,8 @@ an application. For example, if an external database is intended to be used
 for some applicaiton, [k8s-linkup] can be used to make it available to the
 pods running in Kubernetes.
 
+![Screenshot](./screenshot.webp)
+
 This utility is developed alongside the [AlekSIS®] project, to be able to
 link up SaaS-hosted instances to databases hosted elsewhere.