cli: implementing additional testing

[mrestuccia1]

Currently, the testing framework for the CLI is very bare and does not cover many cases. This may lead to missing a lot of bugs, which may go undetected and create issues in the future. We will implement more extensive testing, for new additions (words in quotes, removing prepositions and multiple commands) as well as older elements of the parser. We aim to cover significantly more edge cases, and overall strengthen out testing.

Team Members: Miles, Matteo.