Latest release 20.0.1 doesn't contain "client-java-contrib" module that contains V1 cert-manager models.

**Describe the bug**
Latest client-java release 20.0.1 doesn't contain client-java-contrib module that contains V1 cert-manager models.
and recent cert-manager releases (>= v1.6) doesn't support v1alpha2, v1alpha3, and v1beta1.

**Client Version**
20.0.1

**Kubernetes Version**
N/A

**Java Version**
Java 8

**To Reproduce**
Upgrade cert-manager to >= v1.6 version.

**Expected behavior**
Kubernetes client-java library should support V1 cert-manager models.
https://cert-manager.io/docs/releases/release-notes/release-notes-1.6/.

**KubeConfig**
If applicable, add a KubeConfig file with secrets redacted.

**Server (please complete the following information):**
- OS: [e.g. Linux]
- Environment [e.g. container]
- Cloud [e.g. Azure]

**Additional context**
Add any other context about the problem here.