Streamline unit testing within '.travis.yml'

[jeff1evesque]

We need to streamline the pytest-flask implementation within the .travis.yml. However, it may not be necessary to implement the pytest-flask command via docker containers, given how unit testing was resolved via #2642. If the latter is the case, then involving docker containers may not be an accurate representation of our system until a later milestone, when corresponding docker containers are actually implemented for development, or production environments. However, if the .travis.yml has problems running the equivalent command to launch the pytest, then we can return to #2628, before solving this issue. Otherwise, we'll mark #2628 to a later milestone, and resolve this issue by immediate implementation via .travis.yml.

[jeff1evesque]

This issue would mean we would need to build all the context's necessary for our python application via the .travis.yml, which was an oversight. So, we'll need to return to the idea of resolving #2628, prior to this issue. Otherwise, we'll have a convoluted .travis.yml.