Improve create validation

[mjudeikis]

If cluster is created and failed with non-terminal state in the first phase InstallPhaseBootstrap when dequeued it will get:

ERRO[2021-07-05T08:52:39+01:00]pkg/util/steps/runner.go:34 steps.Run() step [AuthorizationRefreshingAction [Action github.com/Azure/ARO-RP/pkg/cluster.(*manager).validateResources-fm]] encountered error: 400: InvalidLinkedVNet: properties.masterProfi
le.subnetId: The provided subnet '/subscriptions/225e02bc-43d0-43d1-a01a-17e584a4ef69/resourceGroups/v4-westeurope/providers/Microsoft.Network/virtualNetworks/dev-vnet/subnets/mjudeikis-master' is invalid: must not have a network security group attac
hed.  component=backend resource_group=v4-westeurope resource_id=/subscriptions/225e02bc-43d0-43d1-a01a-17e584a4ef69/resourcegroups/v4-westeurope/providers/microsoft.redhatopenshift/openshiftclusters/mjudeikis resource_name=mjudeikis subscription_id=
225e02bc-43d0-43d1-a01a-17e584a4ef69                          

We should make this pass if nsg is ours.