[DOCS] (NMIND bronze) Provide instructions for users to run tests that include instructions for evaluation for correct behavior

[zhao-cy]

In docs of "contributing to BABS", add these instructions:

• [x] how to run pytest locally;
• [x] circle ci will be triggered for commits;
• [x] For things not covered by circle ci, what are the list of the tests to run on a server

Above steps have been discussed w/ @tsalo.

[zhao-cy]

In addition, Matt thinks the current example walkthrough can also fulfill this check.