Import errors in vulnerabilities.importers.gitlab.GitLabAPIImporter

[pombredanne]

parse_yaml_file: affected_range is not parsable: '(,)' type:'nuget' error: InvalidVersion("'None' is not a valid <class 'univers.versions.NugetVersion'>")
 Traceback (most recent call last):
  File "/app/vulnerabilities/importers/gitlab.py", line 220, in parse_gitlab_advisory
    affected_version_range = vrc.from_native(affected_range)
  File "/usr/local/lib/python3.9/site-packages/univers/version_range.py", line 616, in from_native
    VersionConstraint(comparator="=", version=cls.version_class(str(lower_bound)))
  File "<attrs generated init univers.versions.NugetVersion>", line 7, in __init__
    self.__attrs_post_init__()
  File "/usr/local/lib/python3.9/site-packages/univers/versions.py", line 87, in __attrs_post_init__
    raise InvalidVersion(f"{self.string!r} is not a valid {self.__class__!r}")
univers.versions.InvalidVersion: 'None' is not a valid <class 'univers.versions.NugetVersion'>

parse_yaml_file: affected_range is not parsable: '(,)' type:'nuget' error: InvalidVersion("'None' is not a valid <class 'univers.versions.NugetVersion'>")
 Traceback (most recent call last):
  File "/app/vulnerabilities/importers/gitlab.py", line 220, in parse_gitlab_advisory
    affected_version_range = vrc.from_native(affected_range)
  File "/usr/local/lib/python3.9/site-packages/univers/version_range.py", line 616, in from_native
    VersionConstraint(comparator="=", version=cls.version_class(str(lower_bound)))
  File "<attrs generated init univers.versions.NugetVersion>", line 7, in __init__
    self.__attrs_post_init__()
  File "/usr/local/lib/python3.9/site-packages/univers/versions.py", line 87, in __attrs_post_init__
    raise InvalidVersion(f"{self.string!r} is not a valid {self.__class__!r}")
univers.versions.InvalidVersion: 'None' is not a valid <class 'univers.versions.NugetVersion'>

Unknown package type: conan