K8SSAND-1652 ⁃ Use httpGet as liveness / readiness check instead of wget and add a timeout

[burmanm]

What is missing?
We use wget to do the liveness / readiness check for the management-api, without timeout. This might cause the wget calls to hang and they will never return.

There's no reason to do it with wget anymore, Kubernetes these days has httpGet support for the liveness / readiness checks and we should take advantage of that. Management-api should have those resources always available without the need for TLS calls.

Why do we need it?

Environment

• Cass Operator version:

  Insert image tag or Git SHA here

  **Anything else we need to know?**:

┆Issue is synchronized with this Jira Task by Unito
┆Issue Number: K8SSAND-1652
┆priority: Medium
┆Link To Issue: https://k8ssandra.atlassian.net/browse/K8SSAND-1652