Add empty webhooks array to fix error
Add empty webhooks array to fix error

- Without this array set, the admission-webhook reconcile returns an
  error, which causes 2 error log messages and an imediate retry
  (with backoff), until webhooks is added to the
  ValidatingWebhookConfiguration
- With this array, the admission-webhook reconcile returns without
  error and waits for the Secret being updated to include the ca.crt.
  This causes less log spam and fewer errors.

b/237284419

Change-Id: I66e632c51090b6f8b5c4ea98eff73430b5d1f8ab
GitOrigin-RevId: ca3b3eda3485001f4c4a609ca0e8fa5d0982a269

GoogleContainerTools/kpt-config-sync,GoogleContainerTools/kpt-config-sync