Unit test v Integration test

[Hritik14]

Unit tests make sure that functionality of a unit of code doesn't break. It works good for testing functions like to_advisories and comparing it with expected advisories but sometimes the upstream source changes and those are undetectable by unit tests (#423). An integration test that checks the updated_advisories provided with a very small real data source should fix this problem.
Here is how it could be implemented:

• Mock the real data source to return only a small amount of data. It is the responsibility of the test to supply small yet valid data that is actually fetched from the upstream. Valid
• Run the importer against that data source.

This could entirely be avoided by solving #210 and having the entire suit run as one perfect integration test but until that is fixed we can have some small integration tests.

[Hritik14]

Just looked at #365 and it is exactly what suits right now.