Add input sharding unit test

[charlesli640]

Description

Add input shardings dump comparison in unit test.

Tests

python -m pytest tests/unit/sharding_compare_test.py

Checklist

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• I have run end-to-end tests tests and provided workload links above if applicable.
• I have made or will make corresponding changes to the doc if needed, including adding new documentation pages to the relevant Table of Contents (toctree directive) as explained in our documentation.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

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[richjames0]

lgtm