text: Title: [BUG] `use_arrow_dtype` doesn't work when read a directory path for `read_parquet`
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  **Describe the bug**
  `use_arrow_dtype` doesn't work when read a directory path for `read_parquet`
  
  **To Reproduce**
  ``` Python
  In [26]: df = md.read_parquet(tempdir, use_arrow_dtype=True)
  
  In [27]: df.dtypes
  Out[27]: 
  a      int64
  b     object
  c    float64
  dtype: object
  
  ```
  Expected dtypes should be:
  ``` Python
  In [14]: df.dtypes
  Out[14]: 
  a            int64
  b    Arrow[string]
  c          float64
  dtype: object
  ```
  
  
  **Expected behavior**
  A clear and concise description of what you expected to happen.
  
  **Additional context**
  Add any other context about the problem here.
  