[ISSUE] Newly required cfg parameter in ApiClient no longer matches Databricks documentation

[jdavidheiser]

Description
The docs at https://docs.databricks.com/aws/en/files/workspace instruct users to call client = ApiClient() because older versions of the SDK created a default config. In #785, a required cfg parameter was added, so ApiClient no longer correctly assumes a default configuration when running in a notebook (like WorkspaceClient does).

Reproduction
Try to run the notebook in the linked Databricks docs. It will fail with

TypeError: ApiClient.__init__() missing 1 required positional argument: 'cfg'

Expected behavior
Calling ApiClient from a notebook should automatically do the correct thing.

Is it a regression?
Yes

Debug Logs
NA

Other Information
DBR 16.1, SDK version 0.54

Additional context
NA