rootresize: add more tests

Test deploy virtual machine with root resize ... ok
Test proper failure to deploy virtual machine with rootdisksize of 0 ... ok
Test proper failure to deploy virtual machine with rootdisksize less than template size ... ok
Test proper failure to deploy virtual machine with XenServer hypervisor ... ok
Test proper failure to deploy virtual machine with VMware hypervisor ... ok

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Ran 5 tests in 248.033s