[NDM] Add NDM metadata support for Cisco ACI (#17735)

* Add support for sending device metadata

* Add unit test for device metadata, update fixture

* Add license header, changelogs

* Lint

* First pass at submitting interface metadata, cleanup for test fixtures

* Fix for py2.7 support

* Try to fix imports

* Deal with pydantic stuff py2.7

* Allow namespace for Cisco ACI devices, static var for vendor

* Update device metadata to use the correct fieldname, add pydantic model for EvP intake

* Sync the conf.yaml example

* Add device type and integration to device metadata, fix ID field name

* Update interface statuses

* Deal with device status (use fabricSt)

* Update get_eth_list to get operStatus, update all tests and fixtures

* Amend docs for namespace

* Batch events sent to EvP

* Add interface status metric

* Only add to list for >py3.0

* Update default value for vendor, yield for batch events, use device type other

* Add source field to device metadata tags

* Add enums for interface status

* Use correct track type for NDM metadata

* Amend device id tag, collect timestamp ms -> s

* Add interface integration field

* More generic method to send EvP event

* Add docstring for the EvP method

* Update interface tagging, remove system_ip tag

* Fix linting for submit event platform event

* Use interface ID tags b915f56

Author: zoedt