Add a 30 second timeout for all HTTP requests that the webhook sends
so they timeout instead of hanging forever.
Kubernetes-commit: 2de3ee5c48503d3b3214aef55ae7fd0dacc40457
This commit adds tests for pkg/util/webhooks. The purpose of this was
not only for better code coverage but also to alleviate the need for
consumers to write their own tests for core functionality.
Kubernetes-commit: d15dba7e8bff943d91ba6f58fcb0dfefa357a7f1