Use FixedSizeBinary instead of Binary for int96 conversion when convertInt96ToArrowTimestamp is false

### Describe the enhancement requested

```java
public TypeMapping convertINT96(PrimitiveTypeName primitiveTypeName) throws RuntimeException {
if (convertInt96ToArrowTimestamp) {
return field(new ArrowType.Timestamp(TimeUnit.NANOSECOND, null));
} else {
return field(new ArrowType.Binary());
}
}
```
When converting a Parquet type to an Arrow type, if the original type is int96 and the option convertInt96ToArrowTimestamp is set to false, the resulting Arrow type defaults to Binary. However, it might be more appropriate to use FixedSizeBinary instead.

### Component(s)

_No response_