Update ZCP Managed Index & Milvus Index demos

[jaelgu]

Description

Update demos for ZCP managed index & Milvus index:

• ZCP managed index: update notebook to adapt recent changes in llama-index structure.
• Milvus index: update notebook & docstring to support Milvus local (using a local directory as vector storage).

Type of Change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration

• Added new unit/integration tests
• Added new notebook (that tests end-to-end)
• I stared at the code and made sure it makes sense

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[logan-markewich]

We shouldn't have to use llama-index-legacy at all here

This import works fine
from llama_index.core.vector_stores import MetadataFilters, ExactMatchFilter

[jaelgu]

We shouldn't have to use llama-index-legacy at all here

This import works fine from llama_index.core.vector_stores import MetadataFilters, ExactMatchFilter

@logan-markewich Thank you for comments. I've updated the notebook.