Phabsana used to only show priority for Phabricator
without taking into account the value in Asana.
This was fixed by targeting Asana's custom fields

The change adds a unit test and updates the
requirements.txt file, adding pytest to the
list of dependencies.

Though the ticket was resolved in Phabricator, the values
returned by the Phab API were confusing, causing that ticket
to be considered Open, while it should not. The fix was to
determine whether ["fields"]["dateClosed"] is an integer.
If it is, the ticket was closed, otherwise it is still open.

- Tweak Phabricator ID regex
- Unify title between Asana and Phab API in backend
- Remove auto-generated tags from title

Make sure tasks in Phab:Completed column don't
appear unless they differ from the Asana task

- Updated .env.example with additional default settings
- Tweaked Asana and Phabricator services to handle serialization
- Adjusted Task model to serialization