Basing this action on push to `chart-*` tags doesn't work: the action itself
creates the new release tag, so trying to push the changes to a tag ends up
with the releaser comparing the changes to themself (and failing).
This also renames the chart from "descheduler" to "descheduler-helm-chart", to
avoid confusion with automated releases.
This newly documented URL can be used to view the descheduler staging
registry in a web browser. This is easier to browse if the gcloud
command is not available.
Starting with descheduler v0.18 a release branch will be created for
each descheduler minor release. The release guide has been updated with
the steps to create release branches.