Assuming that ProGet has access to inedo.com, ProGet will automatically activate. Otherwise, you will have to manually activate. Activation is required when the CPUID changes or the MAC address changes. So, the easiest thing to do is just to ensure those don't change; these are almost certainly options in the VM Host.
It's possible to programmatically active, but quite bothersome. You'd need to call our (undocumented) product registration endpoint, then add data to the ProGet database, then reset the web application. We don't really support this, and it's quite fragile (i.e. having someone else maintain this as a SOP), so it's best to just ensure the ProGet VM doesn't change and require re-activation.