[devtools] don't hide warnings and errors during tests
The markdown module in jessie turns all warnings into logging calls, so
this allows me to still see deprecation warnings when running tests.
for table, column in [
('transactions', 'tx_time'),
('tx_entity_actions', 'tx_uuid'),
('tx_relation_actions', 'tx_uuid')]:
repo.system_source.create_index(session, table, column)
commit()