Unfortunately there is nothing built in for this. You used the helm tag, so with Helm you do this by setting a checksum of the rendered configmap (or secret, same issue there) as an annotation in the pod template. This means that changing the configmap results in a (meaningless) change to the pod template, which triggers a rolling update.

Consider reloader, a kubernetes controller, that watches changes to configmaps and secrets and will trigger a deployment when there is any change --> https://github.com/stakater/Reloader