cmd/k8s-operator: use correct tailnet client for L7 & L3 ingresses (#18749)

* cmd/k8s-operator: use correct tailnet client for L7 & L3 ingresses

This commit fixes a bug when using multi-tailnet within the operator
to spin up L7 & L3 ingresses where the client used to create the
tailscale services was not switching depending on the tailnet used
by the proxygroup backing the service/ingress.

Updates: https://github.com/tailscale/corp/issues/34561

Signed-off-by: David Bond <davidsbond93@gmail.com>

* cmd/k8s-operator: adding server url to proxygroups when a custom tailnet has been specified

Signed-off-by: chaosinthecrd <tom@tmlabs.co.uk>
(cherry picked from commit 3b21ac5504e713e32dfcd43d9ee21e7e712ac200)

---------

Signed-off-by: David Bond <davidsbond93@gmail.com>
Signed-off-by: chaosinthecrd <tom@tmlabs.co.uk>
Co-authored-by: chaosinthecrd <tom@tmlabs.co.uk>

cmd/k8s-operator/testutils_test.go

@@ -31,9 +31,9 @@ import (
 	"k8s.io/client-go/tools/record"
 	"sigs.k8s.io/controller-runtime/pkg/client"
 	"sigs.k8s.io/controller-runtime/pkg/reconcile"
+
 	"tailscale.com/internal/client/tailscale"
 	"tailscale.com/ipn"
-	"tailscale.com/ipn/ipnstate"
 	tsapi "tailscale.com/k8s-operator/apis/v1alpha1"
 	"tailscale.com/kube/kubetypes"
 	"tailscale.com/tailcfg"
@@ -985,18 +985,3 @@ func (c *fakeTSClient) DeleteVIPService(ctx context.Context, name tailcfg.Servic
 	}
 	return nil
 }
-
-type fakeLocalClient struct {
-	status *ipnstate.Status
-}
-
-func (f *fakeLocalClient) StatusWithoutPeers(ctx context.Context) (*ipnstate.Status, error) {
-	if f.status == nil {
-		return &ipnstate.Status{
-			Self: &ipnstate.PeerStatus{
-				DNSName: "test-node.test.ts.net.",
-			},
-		}, nil
-	}
-	return f.status, nil
-}