webhook server: use tlsconfig from the manager options

the webhook server should use the tlsconfig specified in the manager
options, so users setting tls fields in the manager see their preference
honoured not only for the metrics server but also for the webhook
server.
Core CAPI does this already, here: https://github.com/kubernetes-sigs/cluster-api/blob/55e16f424c0ed8d3739070125d4c32a036997465/main.go#L406

Author: damdo

main.go

@@ -97,7 +97,7 @@ func main() {
 	pflag.CommandLine.AddGoFlagSet(flag.CommandLine)
 	pflag.Parse()
 
-	_, metricsOptions, err := flags.GetManagerOptions(managerOptions)
+	tlsOptions, metricsOptions, err := flags.GetManagerOptions(managerOptions)
 	if err != nil {
 		setupLog.Error(err, "Unable to start manager: invalid flags")
 	}
@@ -151,6 +151,7 @@ func main() {
 		WebhookServer: webhook.NewServer(webhook.Options{
 			Port:    webhookPort,
 			CertDir: webhookCertDir,
+			TLSOpts: tlsOptions,
 		}),
 		HealthProbeBindAddress: healthAddr,
 		EventBroadcaster:       broadcaster,