Add an option to create a linked clone of LXC Containers

[jebarpg]

Describe the bug
A clear and concise description of what the bug is.

I have tried to create a clone of an 'LXC template' but it does not create a link clone. It does a full clone.
How do I create a link clone.

Please see this issue
muhlba91/pulumi-proxmoxve#351

To Reproduce
Steps to reproduce the behavior:

1. Create a resource '....'
2. Run '....'
3. See error
4. Modify the resource '....'
5. Run '....'
6. See error

Please also provide a minimal Terraform configuration that reproduces the issue.

# >>> put your example here <<< #

Expected behavior
A clear and concise description of what you expected to happen.

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

• Single or clustered Proxmox:
• Proxmox version:
• Provider version (ideally it should be the latest version):
• Terraform/OpenTofu version:
• OS (where you run Terraform/OpenTofu from):
• Debug logs (TF_LOG=DEBUG terraform apply):

[bpg]

That will be a new feature for the provider.