Remove or pin use of a deprecated python package, google-cloud

[crwilcox]

https://github.com/ContextLab/quail/blob/8deb8583f113a1f774b1e88916521b625697a83a/docs/doc_requirements.txt#L16

This repository contains a setup.py or requirements.txt file that depends on the google-cloud package. This package is deprecated. If you wish to continue to use this package, please pin the version to google-cloud<0.34.0. If you have more time to dedicate to this, I would advise sorting out which sub-packages you actually rely on and depending on them.

For further information please view this package on PyPI, https://pypi.org/project/google-cloud/