Update DashAIDataset to accept InMemoryTable in constructor

[Irozuku]

Summary

This pull request enhances dataset compatibility by allowing the DashAIDataset class to accept both pa.Table and InMemoryTable instances. This resolves issues in translation task that relies on InMemoryTable.

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Type of Change

Check all that apply like this [x]:

• Backend change
• Frontend change
• CI / Workflow change
• Build / Packaging change
• Bug fix
• Documentation

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Changes (by file)

• dashai/data/dataset.py:
  • Added import for InMemoryTable from datasets.table.
  • Updated the DashAIDataset constructor to accept Union[pa.Table, InMemoryTable] for the table parameter.

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Testing

• Verify that translation task works

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