Add support for specifiedMachineNames parameter

[waynebrantley]

Is your feature request related to a problem? Please describe.
Please add support to pass specifiedMachineNames into this action.

Describe the solution you'd like
The downstream DeploymentRepository(...).create() call in the typescript api client can already accept a specifiedMachineNames parameter. Would like the parameter added to this action and passed into the downstream existing api.