Behavior of decimal array construction with numpy int64 arrays fails, but a list of ints works

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

This is using PyArrow 18.0.0.

It looks like passing an array of `int64` fails when trying to use that as input for constructing a `decimal128` array, while using a Python list of `int` successfully constructs the array.

Reproducible example:

```
In [52]: import pyarrow as pa

In [53]: import numpy as np

In [54]: pa.array(np.array([1]), pa.decimal128(38, 9))
╭─────────────────────────────── Traceback (most recent call last) ────────────────────────────────╮
│ in :1 │
│ │
│ in pyarrow.lib.array:360 │
│ │
│ in pyarrow.lib._ndarray_to_array:87 │
│ │
│ in pyarrow.lib.check_status:92 │
╰──────────────────────────────────────────────────────────────────────────────────────────────────╯
ArrowInvalid: Got bytestring of length 8 (expected 16)

In [55]: pa.array([1], pa.decimal128(38, 9))
Out[55]:

[
1.000000000
]
```

### Component(s)

Python