Adds a new k8s-proxy command to convert operator's in-process proxy to
a separately deployable type of ProxyGroup: kube-apiserver. k8s-proxy
reads in a new config file written by the operator, modelled on tailscaled's
conffile but with some modifications to ensure multiple versions of the
config can co-exist within a file. This should make it much easier to
support reading that config file from a Kube Secret with a stable file name.
The operator's RBAC has had some updates to ensure it can delegate the
impersonation permissions that k8s-proxy requires to run its API Server
proxy in auth mode where it can impersonate users and groups.
Proxies deployed by kube-apiserver ProxyGroups currently work the same as
the operator's in-process proxy. They do not yet leverage Tailscale Services
for presenting a single HA DNS name.
Updates #13358
Change-Id: Ib6ead69b2173c5e1929f3c13fb48a9a5362195d8
Signed-off-by: Tom Proctor <tomhjp@users.noreply.github.com>
