Potential conflicting type checks and dead code in `/src/datasets/table.py`

[rc4typecheck]

When statically analyzing and manually reviewing the code, I noticed a potential logic conflicting in /src/datasets/table.py as follows:

def to_blocks(table: Union[pa.Table, Table]) -> list[list[TableBlock]]:
      if isinstance(table, pa.Table):
          return [[InMemoryTable(table)]]
      elif isinstance(table, ConcatenationTable):  # dead code
          return copy.deepcopy(table.blocks)
      else:
          return [[table]]

Within the function, the condition isinstance(table, ConcatenationTable) at line 4 will never be True because the previous condition isinstance(table, pa.Table) at line 2 would have already caught all instances of ConcatenationTable (since ConcatenationTable is a subtype of pa.Table). This creates a logical conflict in the type checking flow.

Please verify if this logic is intentional or it is an issue warranting a refactoring or fixing.

[lhoestq]

ConcatenationTable is a subclass of datasets.table.Table but not pa.Table, so it should be fine