I am using Version 1.2.7 Deployed via Kube Helm Charts I am getting error on the UI

Operation name: SingleAssetQuery

Message: '<' not supported between instances of 'StaleCauseCategory' and 'StaleCauseCategory'

Path: ["assetOrError","definition","staleCauses"]

Locations: [{"line":55,"column":3}]

Stack Trace:
  File "/usr/local/lib/python3.7/site-packages/graphql/execution/execute.py", line 521, in execute_field
    result = resolve_fn(source, info, **args)
  File "/usr/local/lib/python3.7/site-packages/dagster_graphql/schema/asset_graph.py", line 582, in resolve_staleCauses
    causes = self.stale_status_loader.get_stale_root_causes(self._external_asset_node.asset_key)
  File "/usr/local/lib/python3.7/site-packages/dagster/_core/definitions/data_version.py", line 271, in get_stale_root_causes
    return self._get_stale_root_causes(key=key)
  File "/usr/local/lib/python3.7/site-packages/dagster/_utils/cached_method.py", line 72, in helper
    result = method(self, *args, **kwargs)
  File "/usr/local/lib/python3.7/site-packages/dagster/_core/definitions/data_version.py", line 379, in _get_stale_root_causes
    root_pairs = sorted([pair for cause in causes for pair in self._gather_leaves(cause)])

Hi! Sorry that this happened to you. If it's the same as the one I'm thinking of then, this PR addresses it and it'll be fixed in the next release.