Move existing integrations to use external integration / controller pattern

[Kircheneer]

Proposed Functionality

CVP, DNAC and Infoblox are already or will be soon using the external integration and/or controller models from Nautobot 2.1/2.2 respectively. The other integrations should follow this pattern.

[jdrew82]

To be clear, we'll be updating the following integrations to use either ExternalIntegration or Controller objects:

ACI - Controller
CVP - Controller
D42 - ExternalIntegration
IPFabric - Controller
ServiceNow - ExternalIntegration

[Kircheneer]

Thanks for elaborating!