Pin Version of Azure Cosmos to <4

[kaxil]

Old Repo: https://github.com/Azure/azure-cosmos-python
New Repo: https://github.com/Azure/azure-sdk-for-python/tree/master/sdk/cosmos/azure-cosmos

azure-cosmos==4.0.0 was released on 20 May 2020 that breaks Airflow with Azure dep:

Error:

Traceback (most recent call last):
  File "<string>", line 1, in <module>
    from azure.cosmos.errors import HTTPFailure
ImportError: cannot import name 'HTTPFailure' from 'azure.cosmos.errors'

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[kaxil]

I am not sure why the test is failing:

************* Module airflow.providers.google.cloud.hooks.datacatalog
airflow/providers/google/cloud/hooks/datacatalog.py:519:15: E1101: Class 'DataCatalogClient' has no 'field_path' member (no-member)
airflow/providers/google/cloud/hooks/datacatalog.py:842:15: E1101: Class 'DataCatalogClient' has no 'field_path' member (no-member)
airflow/providers/google/cloud/hooks/datacatalog.py:1217:38: E1101: Class 'DataCatalogClient' has no 'field_path' member (no-member)

[kaxil]

Aah that is because Datacatalogclinet released new version too :(

[kaxil]

Created a followup PR: #8957