clean up / format / poetry (#1000)

* stub in poetry for pipenv

* re-add tester image

* add pre-commit / formatting

* fix ghactions

* revert test data whitespace, exclude tests/data

* revert ws

* decruft, rm tox/pipenv

* install dev packages for base image

* add lgtm config to force to py3

peeringdb_server/management/commands/pdb_delete_pocs.py

@@ -1,9 +1,8 @@
 from datetime import timedelta
 
-from django.core.management.base import BaseCommand
 from django.conf import settings
+from django.core.management.base import BaseCommand
 from django.utils import timezone
-
 from reversion.models import Version
 
 from peeringdb_server.models import NetworkContact