chore: update noxfile.py.j2

* Update noxfile.py.j2

add changes from @glasnt to the template template to ensure that enforcing type hinting doesn't fail for repos with the sample noxfile (aka all samples repos)
See https://github.com/GoogleCloudPlatform/python-docs-samples/pull/4869/files for context

* fix typo

Source-Author: Leah E. Cole <6719667+leahecole@users.noreply.github.com>
Source-Date: Thu Dec 3 13:44:30 2020 -0800
Source-Repo: googleapis/synthtool
Source-Sha: 18c5dbdb4ac8cf75d4d8174e7b4558f48e76f8a1
Source-Link: googleapis/synthtool@18c5dbd

google/pubsub_v1/__init__.py

@@ -90,6 +90,7 @@
     "ModifyPushConfigRequest",
     "PublishRequest",
     "PublishResponse",
+    "PublisherClient",
     "PubsubMessage",
     "PullRequest",
     "PullResponse",
@@ -101,11 +102,10 @@
     "Snapshot",
     "StreamingPullRequest",
     "StreamingPullResponse",
-    "SubscriberClient",
     "Subscription",
     "Topic",
     "UpdateSnapshotRequest",
     "UpdateSubscriptionRequest",
     "UpdateTopicRequest",
-    "PublisherClient",
+    "SubscriberClient",
 )