arrow

GH-34863: [Go] Pow method for Decimal DataTypes (#34864)



### Rationale for this change
Closes: https://github.com/apache/arrow/issues/34863

### Are these changes tested?
Yes

### Are there any user-facing changes?
Yes
* Closes: #34863

Authored-by: izveigor <izveigor@mail.ru>
Signed-off-by: Matt Topol <zotthewizard@gmail.com>