Allow skipping directory checks in `read_parquet`

[hombit]

Feature request

Since we switched to fsspec.parquet.open_parquet_file for our parquet reading code, we added extra round-trips for remote filesystems to check if the destination is a directory. We should allow users to specify if the destination is a directory or a file, so we can skip this check.

I propose to add read_parquet(..., is_dir: bool | None = None), which will perform that check, the same way it is implemented in HATS:
astronomy-commons/hats#601

This would help to resolve this HATS issue:
astronomy-commons/hats#578

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• I have described the purpose of the suggested change, specifying what I need the enhancement to accomplish, i.e. what problem it solves.
• I have included any relevant links, screenshots, environment information, and data relevant to implementing the requested feature, as well as pseudocode for how I want to access the new functionality.
• If I have ideas for how the new feature could be implemented, I have provided explanations and/or pseudocode and/or task lists for the steps.