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

tests/test_cmd_delete_pocs.py

@@ -2,18 +2,16 @@ import io
 from datetime import timedelta
 
 import pytest
-
-from .util import ClientCase, Group
-
-from django.core.management import call_command
-from django.conf import settings
-from django.utils import timezone
-
 import reversion
+from django.conf import settings
+from django.core.management import call_command
+from django.utils import timezone
 from reversion.models import Version
 
 from peeringdb_server.models import Network, NetworkContact
 
+from .util import ClientCase, Group
+
 
 class TestRenumberLans(ClientCase):
     @classmethod