4 of the 600 fixture tests fail: tickets KITE-1000, 1150, 1300 and 1450 have
status 'In progress', which isn't in STATUSES.

tests/fixtures/tickets.json is generated by scripts/make_fixtures.py. Read that
script, tests/test_fixtures.py and tickets/models.py. Don't open tickets.json.
Fix the script, run `python scripts/make_fixtures.py`, then
`python -m pytest -q --tb=short`. Done means 607 passed.
