Add VM Balloning support for Proxmox

roles/virtualization/tasks/proxmox.yml

@@ -13,6 +13,7 @@
     cpu: "host"
     cores: "{{ vm_cpus }}"  # Number of CPU cores
     memory: "{{ vm_memory }}"  # Memory size in MB
+    balloon: "{{ vm_ballo | default(omit) }}"
     numa_enabled: true
     hotplug: "network,disk"
     bios: ovmf