arrow

ARROW-16356: [Python] Expose RandomAccessFile::GetStream (#13793)

This will fix [ARROW-16356](https://issues.apache.org/jira/browse/ARROW-16356), taking over and will close #13144  

Adds `pyarrow.NativeFile.get_stream`, ie:
```python
with pa.PythonFile(io.BytesIO(b'data'), mode='r') as f:
    stream = f.get_stream(file_offset=1, nbytes=3)
    assert stream.read() == b'ata'
```

Lead-authored-by: Miles Granger <miles59923@gmail.com>
Co-authored-by: alexdesiqueira <alex.desiqueira@igdore.org>
Co-authored-by: alexdesiqueira <alexdesiqueira@igdore.org>
Co-authored-by: Alexandre de Siqueira <alex.desiqueira@igdore.org>
Signed-off-by: Antoine Pitrou <pitrou@free.fr>