Parquet Schema Inference only supports File, not directory #2685

When using a FileSource that is in Parquet format, if the source happens to be a directory of partitioned Parquet files, the following lines throw an error:

OSError: Expected file path, but /home/ubuntu/project/data/driver_stats_partitioned is a directory

How to replicate:

1. Start with a demo feast project (feast init)
2. Create a partitioned Parquet Dataset. Use the following to create a dataset with only a single timestamp for inference

import pyarrow.parquet as pq
df = pq.read_table("./data/driver_stats.parquet")
df = df.drop(["created"])
pq.write_to_dataset(df, "./data/driver_stats_partitioned")

3. Update the file source in example.py to look like this:

driver_hourly_stats = FileSource(
    path="/home/ubuntu/cado-feast/feature_store/exciting_sunbeam/data/driver_stats_partitioned2",
)

4. Run feast apply
   For now, I've been able to fix by updating the above lines to:

schema = ParquetDataset(
    path if filesystem is None else filesystem.open_input_file(path)
).schema.to_arrow_schema()