Update and run isort (#9573)

I want to use isort as part of https://github.com/certbot/certbot/issues/9572 because I want to do it programmatically, however, I felt like the config needed to be tweaked a bit due to it not understanding what is and is not our own code.

This PR updates the isort config so it recognizes our own modules and runs `isort .` from the root of the repo to update everything.

* update isort config

* run "isort ."

certbot-dns-google/tests/dns_google_test.py

@@ -1,14 +1,13 @@
 """Tests for certbot_dns_google._internal.dns_google."""
 
 import unittest
+from unittest import mock
 
 from googleapiclient import discovery
 from googleapiclient.errors import Error
 from googleapiclient.http import HttpMock
 from httplib2 import ServerNotFoundError
 
-from unittest import mock
-
 from certbot import errors
 from certbot.compat import os
 from certbot.errors import PluginError