Update container/snippets/noxfile.py
Update container/snippets/noxfile.py

Co-authored-by: nicain <9b4b81b0bdce5d3a5b26f1d553bed3acfed2c6ad@google.com>
GoogleCloudPlatform/python-docs-samples,GoogleCloudPlatform/python-docs-samples,GoogleCloudPlatform/python-docs-samples,GoogleCloudPlatform/python-docs-samples