When a citation.cff file contains a preferred-citation field, ensure
citation metadata are extracted from it.

Resolves #4743.

It's now expected the sql/ directory to live in the module implementing
the swh.core.db based backend.

But do not fail if no config file is given by default; required to be able
to run 'swh indexer mapping list-terms' for example (which is used to build the
documentation).

Normalize the indexer storage db for swh.core 3.6 with improved `swh db` handling
capabilities.

Remove storage/test_init.py, it's now outdated.

Warning: this rename the config entry for indexer storages from
'indexer_storage' to 'indexer.storage'. Bw compat core handle this when
loading the configuration for indexer cli tools and the api server only;
generic loading mechanism will not handle the old name properly
(i.e. when managing the storage db using `swh db` commands).

rdflib implicitly sets xsd:integer as the type of Literal(42); while the
ActivityStream specification requires a xsd:nonNegativeInteger here.

This was highlighted by a bugfix in rdflib 7.1.0, as previous versions
omitted serializing the "default" datatype corresponding to the Python
type of the literal value when writing in JSON-LD.

This is only a workaround until these tests are properly fixed.
They should probably be converted as actual (py)tests; it would make it
easier to support these types of breakage due to formatting changes in
rdflib...

Catch parsing error exceptions when attempting to parse a codemeta
document in XML or JSON then print error log and return None.

Fixes #4738
for existing metadata objects

Since the release of pytest 8.1, some pytest options are no longer
needed and editable install can be used when running tests using tox.

Related to swh/meta#5075.

Most other journal clients use this configuration key

Celery tasks for indexer were removed so we also need to stop referencing
them in the swh.workers entrypoint.

And replace comment type annotations by explicit ones.

Docstring is mandatory for a celery task function as its value
is inserted in the required description column of the task_type
table in the scheduler database.

Celery task function name is also used as task name (with underscores
replaced by dashes) so ensure task function names match the task types
registered in production scheduler database.

So that we can get rid of indexer task types being created by
swh-schedulers' sql init scripts.