Leaked Kubernetes resources when a service-name / service-hostname changes

The nginx-ingress-integrator charm creates Kubernetes resources (Services and Ingress Resources) based on the configured service-name and service-hostname.

However, if the charm is then configured with a different service-name and service-hostname, the previous resources are not removed. This happens everytime the configuration options change since the Resource names are based on the aforementioned service-name / service-hostname.

This can also happen for the service-names and service-hostnames received from relation data (+ additional-hostnames for Ingress Resources). This issue occurs on previous revisions as well.

Because the Kubernetes resource names are based on service-name / service-hostname, cleaning them up is not immediately straight-forward since the charm would have to store the previous values and compare them to the current ones.