WIP: Add Azure kubeadm clusterclass example

[valaparthvi]

kind/enhancement

What this PR does / why we need it:
This PR adds Azure Kubeadm clusterclass example. This is taken from the clusterclass template provided by https://github.com/kubernetes-sigs/cluster-api-provider-azure and modified a little to suite our requirements.

The test is currently flaky and do not work well for Control Plane replicas > 1 (3 for e.g.).
It also does not always work with replicas: 1; the issue might be related to the race condition between CAAPF and Rancher Turtles; because the fleet-agent bundle to be deployed on the workload cluster is continuously applied (deleted and recreated); this problem is fixed when the replica count for CAAPF deployment is brought down to 0 (this change is reverted automatically).

But the race condition is not present for CAPZ RKE2, so it is perhaps Kubeadm specific or has to do with our definition.

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #1330

Special notes for your reviewer:

Checklist:

• squashed commits into logical changes
• includes documentation
• adds unit tests
• adds or updates e2e tests