Update needed for Netbox 4.0

[DatPenguin]

Hi,

There are some breaking changes in Netbox 4.0, including the following:

from extras.plugins import PluginConfig should be replaced by from netbox.plugins import PluginConfig.

I'm not sure what else needs to be changed, but is an update planned to be compatible with Netbox 4.0 ? Thanks :)

P.S.: Here are the changes from Netbox Doc.