Repository webhook on branch

[Dor Mull-or]

Hi all,
I would like to know if there is a way to trigger a webhook event when a branch closes?

The reason I need this is that we want to work with dynamic namespaces in Kubernetes.
Each branch creation triggers a webhook that eventually creates a new namespace in Kubernetes and automatically deploys the branch application version.
For the creation, I used the "push to repository" event webhook.
For keeping my Kubernetes cluster clean, I need to close this namespace at the moment the branch is no longer exists.