Make `datafusion` read parquet folders if non parquet files exists

[comphead]

Create test data

ls -la /tmp/t1

-rw-r--r--@  1 xxx  wheel   12 Jun  6 08:35 .part-00000-e248d995-5eac-404e-a2ed-0eb16e27c005-c000.snappy.parquet.crc
-rw-r--r--@  1 xxx  wheel  455 Jun  6 08:35 part-00000-e248d995-5eac-404e-a2ed-0eb16e27c005-c000.snappy.parquet

• should realize this is a folder and rewrite as /tmp/t1/*.parquet

DataFusion CLI v47.0.0
CREATE EXTERNAL TABLE t1 STORED AS PARQUET location '/tmp/t1';
Parquet error: Parquet error: Invalid Parquet file. Corrupt footer

Originally posted by @comphead in #13456

[comphead]

Surprisingly if I try same tests in DF itself using unit or slt tests, it works. Looks like the issue in datafusion-cli only

[hendrikmakait]

take

[alamb]

I suspect datafusion-cli tried to read .crc as a parquet file...

[hendrikmakait]

That's what it looks like, I couldn't reproduce the problem with a directory that only contains .parquet files (or Parquet-compatible files with different extensions).

[comphead]

good catch, putting another file to the folder crashes tests as well.
I'll update the header

[comphead]

I played little bit yesterday in #16487

Feel free to explore, hope it helps

[comphead]

@hendrikmakait you can create a non-parquet file in the test, using write_csv or just create a random txt file

[hendrikmakait]

As a side note, the docs at https://github.com/apache/datafusion/blob/a91e0421ebadf3a155508e28e272f5fb8356bca1/docs/source/user-guide/cli/datasources.md#parquet don't match the current behavior (no trailing / is needed) and will need further updates after implementing this change.

[comphead]

@hendrikmakait sorry I took the liberty to wrap my PR up, please feel free to review