Bigquery version 2.x is no longer supported, but a few labs still explicitly install version 2.x or below.

I ran into [this issue](https://github.com/googleapis/python-bigquery/issues/1842) while doing a machine learning lab. Per chalmerlowe, version 2 has not been supported for almost a year. Despite this, there are still mentions of version 2 throughout this repo. And because version 2 is not supported, the shapely issue isn't going to be fixed either, which means that some labs cannot be completed without removing the bigquery version 2 requirement.

With the following search query:

repo:GoogleCloudPlatform/training-data-analyst !pip install --user /google-cloud-bigquery==1.*/ OR !pip install --user /google-cloud-bigquery==2.*/ language:"Jupyter Notebook"

we can see that there are currently 6 jupyter notebooks with mentions of version 2.x or 1.x.