…rtual_machine` block

…atures block

…ult in 3.0

We can't do this now since the API errors if this preview functionality isn't enabled

…irtual Machine prior to deletion

This is necessary since there's cost benefits to doing so with larger machines - whilst we could opt
to do this automatically in the case of Force Delete based on the Service Teams description of this
functionality, Force Delete should likely become the default in 3.x since it's more reliable for
other items in the stack than a regular delete, however this can't be done yet until the feature
leaves the preview period (as at the moment it's a public preview which errors if it's disabled)

Ultimately this allows users who want to use Force Delete without shutting the VM can do so using
both feature toggles together - whilst allowing the more resilient deletion (which will become
the default at some point in the future) to be used with a gradual shut-down in the case of specific
VM's where this can be useful.