experimental-keystone-url and experimental-keystone-ca-file were always
experimental. So we don't need a deprecation period.
KeystoneAuthenticator was on the server side and needed userid/password
to be passed in and used that to authenticate with Keystone. We now
have authentication and authorization web hooks that can be used. There
is a external repo with a webook for keystone which works fine along
with the kubectl auth provider that was added in:
a0cebcb559c5c0ab8a2e50b1ee11cc62f9ebb3a8
So we don't need this older style / hard coded / experimental code
anymore.
Kubernetes-commit: 18590378c4491eacdea5cd05f98c92fe84020263
This change migrates the 'openstack' provider and 'keystone'
authenticator plugin to the newer gophercloud/gophercloud library.
Note the 'rackspace' provider still uses rackspace/gophercloud.
Fixes#30404