Unable to replicate results from the tutorials

[v-somanath]

The tutorials here don't work readily, with a few errors arising from how the main functions are created.

• NameError: name 'use_late_chunking' is not defined It seems like late_chunking is to be defined, but it's not.
• ValueError: Missing required parameter 'azure_openai_config' for ppi. Though the parameter is optional, it is not possible to configure ppi without azure creds.
• Azure creds are required even when a custom model is being specified.