[Python][Parquet] RowGroupMetadata.total_byte_size computes wrong uncompressed size

### Describe the bug, including details regarding any error messages, version, and platform.

The `RowGroupMetadata.total_byte_size` property is supposed to compute the uncompressed file size:
https://github.com/apache/arrow/blob/7c3d4867e40dd0100542247a61cb83520369b2d4/python/pyarrow/_parquet.pyx#L975-L978

But on a [specific file from parquet-testing](https://github.com/apache/parquet-testing/blob/master/data/alltypes_plain.snappy.parquet) I've found that is computing the compressed size, see:
```python
>>> import pyarrow.parquet as pq
>>> reader = pq.ParquetFile('../datanomy-extra/raulcd_local/data/02-alltypes_plain.snappy.parquet')
>>> rg = reader.metadata.row_group(0)
>>> rg.total_byte_size
570
>>> sum(rg.column(j).total_compressed_size for j in range(rg.num_columns))
570
>>> sum(rg.column(j).total_uncompressed_size for j in range(rg.num_columns))
532
```
For a different parquet test file on datanomy is able to compute it correctly, the file is generated here:
```python
@pytest.fixture
def simple_parquet(tmp_path: Path) -> Path:
"""Create a simple test Parquet file with basic types.

Returns:
Path to the created Parquet file
"""
table = pa.table(
{
"id": [1, 2, 3, 4, 5],
"name": ["Alice", "Bob", "Charlie", "David", "Eve"],
"age": [25, 30, 35, 40, 45],
"score": [85.5, 90.0, 78.5, 92.0, 88.5],
}
)
file_path = tmp_path / "simple.parquet"
pq.write_table(table, file_path)
return file_path
```

### Component(s)

Parquet, Python