python example should use latest current driver version

Description

Pymongo Driver docs include an example installation:

python -m pip install pymongo==3.5.1

In order to avoid reader confusion and to improve convenience, the listed version should be the current latest version of the driver. Currently:

python -m pip install pymongo==3.11

Scope of changes

Change code block to install latest version.

Impact to Other Docs

MVP (Work and Date)

Resources (Scope or Design Docs, Invision, etc.)