Providing no credentials to AzureBlobStorageCredentials raises wrong error message

[serinamarie]

When I don't provide anything to my AzureBlobStorageCredentials:

e.g.

credentials = AzureBlobStorageCredentials()

I get this error:

❯ python qa.py
Traceback (most recent call last):
  File "/Users/bean/code-oss/prefect-azure/qa.py", line 6, in <module>
    credentials = AzureBlobStorageCredentials(
  File "/Users/bean/code-oss/prefect-azure/azurevenv/lib/python3.10/site-packages/prefect/blocks/core.py", line 265, in __init__
    super().__init__(*args, **kwargs)
  File "/Users/bean/code-oss/prefect-azure/azurevenv/lib/python3.10/site-packages/pydantic/v1/main.py", line 341, in __init__
    raise validation_error
pydantic.v1.error_wrappers.ValidationError: 1 validation error for AzureBlobStorageCredentials
__root__
  Must provide either a connection string or account URL, but not both. (type=value_error)

Because the validator is only doing an xor check, not checking that one of the values is True.

@root_validator
def check_connection_string_or_account_url(
    cls, values: Dict[str, Any]
) -> Dict[str, Any]:
    """
    Checks that either a connection string or account URL is provided, not both.
    """
    has_account_url = values.get("account_url") is not None
    has_conn_str = values.get("connection_string") is not None
    if not bool(has_account_url ^ has_conn_str):
        raise ValueError(
            "Must provide either a connection string or account URL, but not both."
        )
    return values