This series of commits, along with their counterparts in swh-archiver, swh-indexer,
swh-scheduler, swh-storage and swh-vault is the firt step for T1265 (aka kill
swh-storage-datatest).
we aim at removing the need for the swh-storage-testdata/dumps files in
any test that reauire a pg database.
For this we build the required db based on sql files now shipped within the
python package. This require several refactorings of
SingleDbTestFixture.setUpClass and .add_db() methods:
- replace the 2 arguments (dump, dump_type) by a single 'dumps' one; this later must be an iterable of couples (dump_file, dump_type)
- refactor all needed helper functions accordingly.
We also add a small helper function to sort numerical file names, and provide a
DB_DUMP_TYPES as a global variable to prepare the next commit in which a new
cli tool 'swh-db-init' is added.
We also provide a new generic swh-db-init cli tool used to initialise a
database for a given (swh) module, like:
swh-db-init storage
Related to T1265.