ubuntu_osv_importer_v2 failing

```
./manage.py import ubuntu_osv_importer_v2
Importing data using ubuntu_osv_importer_v2
INFO 2026-04-28 08:12:59.756077 UTC Pipeline [UbuntuOSVImporterPipeline] starting
INFO 2026-04-28 08:12:59.756154 UTC Step [clone] starting
INFO 2026-04-28 08:12:59.756181 UTC Cloning `git+https://github.com/canonical/ubuntu-security-notices/`

git clone --filter=blob:none https://github.com/canonical/ubuntu-security-notices/ /var/folders/l1/tbpy9vkn2151gnkf324c1bdm0000gr/T/tmp97e0kyr8/checkout exited with 128
INFO 2026-04-28 08:24:27.092971 UTC Pipeline failed
INFO 2026-04-28 08:24:27.093272 UTC Running [on_failure] tasks
Traceback (most recent call last):
File "/Users/neo/contrib/vulnerablecode/vulnerabilities/pipelines/__init__.py", line 111, in execute
step(self)
~~~~^^^^^^
File "/Users/neo/contrib/vulnerablecode/vulnerabilities/pipelines/v2_importers/ubuntu_osv_importer.py", line 48, in clone
self.vcs_response = fetch_via_vcs(self.repo_url)
~~~~~~~~~~~~~^^^^^^^^^^^^^^^
File "/Users/neo/contrib/vulnerablecode/venv/lib/python3.14/site-packages/fetchcode/vcs/__init__.py", line 68, in fetch_via_vcs
backend.obtain(dest=dest_dir, url=misc.hide_url(url), verbosity=1)
~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/Users/neo/contrib/vulnerablecode/venv/lib/python3.14/site-packages/fetchcode/vcs/pip/_internal/vcs/versioncontrol.py", line 502, in obtain
self.fetch_new(dest, url, rev_options, verbosity=verbosity)
~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/Users/neo/contrib/vulnerablecode/venv/lib/python3.14/site-packages/fetchcode/vcs/pip/_internal/vcs/git.py", line 277, in fetch_new
self.run_command(
~~~~~~~~~~~~~~~~^
make_command(
^^^^^^^^^^^^^
...<5 lines>...
)
^
)
^
File "/Users/neo/contrib/vulnerablecode/venv/lib/python3.14/site-packages/fetchcode/vcs/pip/_internal/vcs/versioncontrol.py", line 631, in run_command
return call_subprocess(
cmd,
...<9 lines>...
stdout_only=stdout_only,
)
File "/Users/neo/contrib/vulnerablecode/venv/lib/python3.14/site-packages/fetchcode/vcs/pip/_internal/utils/subprocess.py", line 209, in call_subprocess
raise error
fetchcode.vcs.pip._internal.exceptions.InstallationSubprocessError: git clone --filter=blob:none https://github.com/canonical/ubuntu-security-notices/ /var/folders/l1/tbpy9vkn2151gnkf324c1bdm0000gr/T/tmp97e0kyr8/checkout exited with 128

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/Users/neo/contrib/vulnerablecode/./manage.py", line 6, in
command_line()
~~~~~~~~~~~~^^
File "/Users/neo/contrib/vulnerablecode/vulnerablecode/__init__.py", line 98, in command_line
execute_from_command_line(sys.argv)
~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^
File "/Users/neo/contrib/vulnerablecode/venv/lib/python3.14/site-packages/django/core/management/__init__.py", line 442, in execute_from_command_line
utility.execute()
~~~~~~~~~~~~~~~^^
File "/Users/neo/contrib/vulnerablecode/venv/lib/python3.14/site-packages/django/core/management/__init__.py", line 436, in execute
self.fetch_command(subcommand).run_from_argv(self.argv)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^
File "/Users/neo/contrib/vulnerablecode/venv/lib/python3.14/site-packages/django/core/management/base.py", line 420, in run_from_argv
self.execute(*args, **cmd_options)
~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^
File "/Users/neo/contrib/vulnerablecode/venv/lib/python3.14/site-packages/django/core/management/base.py", line 464, in execute
output = self.handle(*args, **options)
File "/Users/neo/contrib/vulnerablecode/vulnerabilities/management/commands/import.py", line 45, in handle
self.import_data(validate_importers(sources))
~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/Users/neo/contrib/vulnerablecode/vulnerabilities/management/commands/import.py", line 65, in import_data
status, error = importer().execute()
~~~~~~~~~~~~~~~~~~^^
File "/Users/neo/contrib/vulnerablecode/vulnerabilities/pipelines/__init__.py", line 116, in execute
self.on_failure()
~~~~~~~~~~~~~~~^^
File "/Users/neo/contrib/vulnerablecode/vulnerabilities/pipelines/v2_importers/ubuntu_osv_importer.py", line 81, in on_failure
self.clean_downloads()
~~~~~~~~~~~~~~~~~~~~^^
File "/Users/neo/contrib/vulnerablecode/vulnerabilities/pipelines/v2_importers/ubuntu_osv_importer.py", line 76, in clean_downloads
if self.vcs_response:
^^^^^^^^^^^^^^^^^
AttributeError: 'UbuntuOSVImporterPipeline' object has no attribute 'vcs_response'
```

This is a possible git error

```
git clone --filter=blob:none https://github.com/canonical/ubuntu-security-notices/ /var/folders/l1/tbpy9vkn2151gnkf324c1bdm0000gr/T/tmp97e0kyr8/checkout exited with 128
```

Probably due to low storage or other issues

```
(venv) ; df /var/folders/l1/tbpy9vkn2151gnkf324c1bdm0000gr/T/tmp97e0kyr8/checkout -h
Filesystem Size Used Avail Use% Mounted on
/dev/disk3s1s1 461G 461G 376M 100% /
```

In either case, we should provide a better error