:sparkles: change endpoint from string to netbox vm

[lvenier]

Netbox version	Plugin Version	Agent version	Docker API Version
3.7.1	1.6.2	19.0	1.43

Actual Behavior

During the creation of a host agent endpoint as the following description :

it does not allow to link the host to any netbox assets

Desired Behavior

I believe we should create a docker host based on a VM. We should be able to select the vm from the list and we can then have link to netbox assets. I would then be able to know if disabling a port is affecting a container for instance.

Proposal :

VM would be a dropdown from the virtualization/virtual-machines list

This one is a level further of https://github.com/SaaShup/netbox-docker-plugin/issues/91. I think we can close 91 and keep this one instead.