Fix typo in property name

[mrkn]

Fixes the following error introducing by yesterday's commit 718e1f5:

AttributeError: 'OpensearchVectorClient' object has no attribute 'os_version'
Python stacktrace:
 [1] _is_efficient_filtering_enabled
   @ llama_index.vector_stores.opensearch.base ~/.cache/pypoetry/virtualenvs/rag-company-rules-q2Dy5nHQ-py3.11/lib/python3.11/site-packages/llama_index/vector_stores/opensearch/base.py:637
 [2] __init__
   @ llama_index.vector_stores.opensearch.base ~/.cache/pypoetry/virtualenvs/rag-company-rules-q2Dy5nHQ-py3.11/lib/python3.11/site-packages/llama_index/vector_stores/opensearch/base.py:126

Description

Please include a summary of the change and which issue is fixed. Please also include relevant motivation and context. List any dependencies that are required for this change.

Fixes # (issue)

New Package?

Did I fill in the tool.llamahub section in the pyproject.toml and provide a detailed README.md for my new integration or package?

• Yes
• No

Version Bump?

Did I bump the version in the pyproject.toml file of the package I am updating? (Except for the llama-index-core package)

• Yes
• No

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?

Your pull-request will likely not be merged unless it is covered by some form of impactful unit testing.

• I added new unit tests to cover this change
• I believe this change is already covered by existing unit tests

Suggested Checklist:

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added Google Colab support for the newly added notebooks.
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• I ran make format; make lint to appease the lint gods

[mrkn]

@Aydin-ab Could you please have a look this?

[nerdai]

Can you bump version as well.

[mrkn]

@nerdai The version was bumped.

[nerdai]

LGTM thanks!

[nerdai]

Thanks for the fix. Going to ignore Coverall's check for this integration for now.