Advisory lock in match_or_create_house() is now the first db.execute() call;
existing tests built side_effect lists assuming the tier query was first,
causing each to read off-by-one (Tier 0 cadastr lookup gets None, falls
through, etc.).
Prepend a None row to all 5 test_match_house_* _make_db lists. Add
test_match_house_advisory_lock_called_first as a regression guard against
future re-ordering of the lock call.
Per PR #501 reviewer feedback.
