feat(vm-provision): declare the guest agent per guest OS, Linux only

Follows napalm-device-types 3.0, which replaces GUEST_AGENT_PACKAGES /
GUEST_AGENT_RUNCMD with GUEST_AGENTS = {guest_os: (packages, runcmd)}.
VMware lists Linux with open-vm-tools, as before, and refuses any other
guest_os before anything is created: BSD guests on VMware are optional
for now (NetOrk/netork#801).

The NoCloud network-config moved to napalm-device-types
(`provisioning.network_config`), which Proxmox now uses as well; the seed
module's copy is gone, and the tests check that the generic one is used.

napalm_vmware/provision/seed.py

@@ -31,20 +31,6 @@ def meta_data(hostname: str, instance_id: str) -> str:
     return yaml.safe_dump({"instance-id": instance_id, "local-hostname": hostname}, sort_keys=False)
 
 
-def network_config(nics: list[tuple[str, bool]]) -> dict[str, Any] | None:
-    """Netplan v2 config: DHCP on every ``(mac, dhcp)`` NIC that asks for it.
-
-    ``None`` when no NIC does -- cloud-init then leaves networking alone
-    rather than being told to configure nothing.
-    """
-    ethernets = {
-        f"nic{i}": {"match": {"macaddress": mac}, "dhcp4": True}
-        for i, (mac, dhcp) in enumerate(nics)
-        if dhcp
-    }
-    return {"version": 2, "ethernets": ethernets} if ethernets else None
-
-
 def nocloud_iso(user: str, meta: str, network: dict[str, Any] | None) -> bytes:
     """An ISO 9660 image (Rock Ridge + Joliet) holding the seed files."""
     files = {"user-data": user, "meta-data": meta}