Upgrade HCIBox to use 2311.2 as default OS image

[rpsqrd]

Is your issue related to a Jumpstart scenario, ArcBox, HCIBox, or Agora?
HCIBox

Describe the issue or the bug
HCIBox currently installs a pre-GA version of 23H2: 2311.0.26. This version has known issues with the Arc agent in VMs deployed by the resource bridge that will prevent extension management and policy scenarios. These issues have been fixed in 2311.2 and later versions.

You can get around it today by updating the HCI cluster once HCIBox setup is complete and waiting to deploy any Arc VMs until the update is complete.

To Reproduce
Set up HCIBox, deploy a VM with guest management enabled, and try to install a VM extension. It will get stuck in the "creating" state indefinitely. If you run "azcmagent show" on the VM, you'll see the resource name is incorrect and has the VMId appended to the actual resource name, creating a mismatch.

Expected behavior
HCIBox should install the GA version of AzSHCI and extensions should install successfully on HCI VMs.

Environment summary

Have you looked at the Troubleshooting and Logs section?

Screenshots

Additional context