Fix parquet reading from zip or s3

[takacsd]

This fixes #1916 and provides a nicer fix for #1913.

I'm new here so I'm not entirely sure this doesn't brake something, but I tested loading csv and parquet files from a local folder, from a zip and from s3, and all combinations worked... ;)

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[CLAassistant]

All committers have signed the CLA.

[saulpw]

Thanks @takacsd! This looks reasonable. I'll let @anjakefala look over it and make sure it doesn't break anything else, and if not, we'll definitely take it! It'll be nice to fix #1916.

[anjakefala]

Everything seems fine!