cmd/k8s-operator: configure all proxies with declarative config (#11238)

Containerboot container created for operator's ingress and egress proxies
are now always configured by passing a configfile to tailscaled
(tailscaled --config <configfile-path>.
It does not run 'tailscale set' or 'tailscale up'.
Upgrading existing setups to this version as well as
downgrading existing setups at this version works.

Updates tailscale/tailscale#10869

Signed-off-by: Irbe Krumina <irbe@tailscale.com>

cmd/k8s-operator/deploy/manifests/userspace-proxy.yaml

@@ -20,5 +20,3 @@ spec:
           env:
             - name: TS_USERSPACE
               value: "true"
-            - name: TS_AUTH_ONCE
-              value: "true"