"No attribute get_task_types" error on scheduler's task_type cli

swhscheduler@scheduler0:~$ swh scheduler task-type list
WARNING:swh.core.cli:Could not load subcommand storage: No module named 'swh.journal'
Known task types:
Traceback (most recent call last):
  File "/usr/bin/swh", line 11, in <module>
    load_entry_point('swh.core==0.2.3', 'console_scripts', 'swh')()
  File "/usr/lib/python3/dist-packages/swh/core/cli/__init__.py", line 122, in main
    return swh(auto_envvar_prefix="SWH")
  File "/usr/lib/python3/dist-packages/click/core.py", line 764, in __call__
    return self.main(*args, **kwargs)
  File "/usr/lib/python3/dist-packages/click/core.py", line 717, in main
    rv = self.invoke(ctx)
  File "/usr/lib/python3/dist-packages/click/core.py", line 1137, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/usr/lib/python3/dist-packages/click/core.py", line 1137, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/usr/lib/python3/dist-packages/click/core.py", line 1137, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/usr/lib/python3/dist-packages/click/core.py", line 956, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/usr/lib/python3/dist-packages/click/core.py", line 555, in invoke
    return callback(*args, **kwargs)
  File "/usr/lib/python3/dist-packages/click/decorators.py", line 17, in new_func
    return f(get_current_context(), *args, **kwargs)
  File "/usr/lib/python3/dist-packages/swh/scheduler/cli/task_type.py", line 82, in list_task_types
    ctx.obj["scheduler"].get_task_types(), key=lambda x: x["type"]
AttributeError: 'NoneType' object has no attribute 'get_task_types'

The current version is 0.5.2

swhscheduler@scheduler0:~$ dpkg -l python3-swh.scheduler
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name                  Version              Architecture Description
+++-=====================-====================-============-=================================
ii  python3-swh.scheduler 0.5.2-1~swh1~bpo10+1 all          Software Heritage Scheduler

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Migrated from T2574 (view on Phabricator)