Allow ignore_metadata when creating pandas

[delucchi-cmu]

Bug report

I've been debugging the following LSDB issue: astronomy-commons/lsdb#1265

Here's what I think is happening.

The data is older (imported with hats v0.4.0), and still contains pandas metadata inside the parquet files. While newer files will have this metadata suppressed, it's not a guarantee that these will be missing.

This automatically sets the index to _healpix_29, based on the pandas metadata. This is also true in the _ddf.meta.

I would like npd.read_parquet to return to me a nested frame that has no index set, and I believe that's not currently possible.

nested_pandas version: '0.6.8'

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[hombit]

@delucchi-cmu would it basically mean that we should return df.reset_index(drop=False)? Could/should it be done on the hats side instead? Would it work for you if we add a new argument, e.g. read_parquet(ignore_pandas_metadata: bool = False)?

[delucchi-cmu]

I would prefer the ignore_pandas_metadata option, as the index is not the only thing that may be inconsistent in the pandas metadata hiding in the parquet file.