Regression from #6490

[dchristidis]

Description

As reported on Mattermost:

Traceback (most recent call last):
  File "/usr/local/bin/rucio", line 39, in <module>
    from rucio.client import Client
  File "/usr/local/lib/python3.9/site-packages/rucio/client/__init__.py", line 16, in <module>
    from .client import Client  # noqa: F401
  File "/usr/local/lib/python3.9/site-packages/rucio/client/client.py", line 30, in <module>
    from rucio.client.metaconventionsclient import MetaConventionClient
  File "/usr/local/lib/python3.9/site-packages/rucio/client/metaconventionsclient.py", line 24, in <module>
    from rucio.db.sqla.constants import KeyType
ModuleNotFoundError: No module named 'rucio.db'

Steps to reproduce

Use the RC Rucio client, with any subcommand.

Rucio Version

40.0.0rc2

Additional Information

No response

[voetberg]

Took me a second to figure out how this happened. For the future, is there a good suite of tests for client only mode?