Use pyarrow.Table.replace_schema_metadata instead of pyarrow.Table.cast
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This PR partially addresses #2252.

``update_metadata_with_features`` uses ``Table.cast`` which slows down ``load_from_disk`` (and possibly other methods that use it) for very large datasets. Since ``update_metadata_with_features`` is only updating the schema metadata, it makes more sense to use ``pyarrow.Table.replace_schema_metadata`` which is much faster. This PR adds a ``replace_schema_metadata`` method to all table classes, and modifies  ``update_metadata_with_features`` to use it instead of ``cast``.
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