ipn/ipnlocal: delete useless SetControlClientGetterForTesting use

Updates #11649

Change-Id: I56c069b9c97bd3e30ff87ec6655ec57e1698427c
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>

ipn/ipnlocal/local_test.go

@@ -825,16 +825,6 @@ func TestStatusPeerCapabilities(t *testing.T) {
 	}
 	b := newTestLocalBackend(t)
 
-	var cc *mockControl
-	b.SetControlClientGetterForTesting(func(opts controlclient.Options) (controlclient.Client, error) {
-		cc = newClient(t, opts)
-
-		t.Logf("ccGen: new mockControl.")
-		cc.called("New")
-		return cc, nil
-	})
-	b.Start(ipn.Options{})
-	b.StartLoginInteractive()
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
 			b.setNetMapLocked(&netmap.NetworkMap{