GOAL:
I was reading through the API documentation and noticed that there were a few inconsistencies with imports of sinon and usage. I have added the explicit imports of sinon to the relevant places in the documentation. I believe this is a valuable addition because it will remove any ambiguity from the code examples.

CURRENT:
Currently, there are a couple of API docs where code examples are using sinon without an explicit import. The main docs page explicitly imports sinon and this change will make it consistent throughout all the docs.

IMPACT:
This will remove ambiguity from the docs and explicitly mention other dependencies for the code samples.