slcli vlan cancel should report if a vlan is automatic

[caberos]

#1489

[FernandoOjeda]

Do not forget to add unit test for the new methods implemented.

[allmightyspiff]

Change the logic of CLI/vlan/cancel.py to something like this:

reasons = mgr.get_cancel_failure_reasons(identifier)
if len(reasons) > 0:
    raise exceptions.CliAbort(reasons )
item = mgr.get_vlan(identifier).get('billingItem')
if item:
    billing.cancel_item(item.get('id'), 'cancel by cli command')
else:
    raise exceptions.CliAbort("VLAN is an automatically assigned and free of charge VLAN, it will automatically be removed from your account when it is empty")

[allmightyspiff]

Changes look good, thanks.

[FernandoOjeda]

Looks good.

[ATGE]

Testing

• ✔️slcli vlan cancel 1234556
• ✔️slcli -v -y vlan cancel 1234556
• ✔️slcli vlan cancel -h'
  -✔️ slcli vlan -h

looks good, just a comment on cancel cli method docs.