arrow

GH-34590: [C++][ORC] Fix timestamp type mapping between orc and arrow (#34591)

### Rationale for this change

Background: There was an effort to fix inconsistent timestamp types across different SQL-on-Hadoop engines: https://docs.google.com/document/d/1gNRww9mZJcHvUDCXklzjFEQGpefsuR_akCDfWsdE35Q

In the Apache Orc, two timestamp types are provided:

- TIMESTAMP: timestamp type without timezone, timestamp value is stored in the writer timezone .
- TIMESTAMP_INSTANT: timestamp type with local timezone, timestamp value is stored in the UTC timezone.

arrow::TimestampType has an optional timezone field:
- If timezone is provided, values are normalized in UTC.
- If timezone is missing, values can be in any timezone.

### What changes are included in this PR?

The type mapping is fixed as below:
- orc::TIMESTAMP <=> arrow::TimestampType w/o timezone
- orc::TIMESTAMP_INSTANT <=> arrow::TimestampType w/ timezone

### Are these changes tested?

Make sure all tests pass.

### Are there any user-facing changes?

No.
* Closes: #34590

Authored-by: Gang Wu <ustcwg@gmail.com>
Signed-off-by: Will Jones <willjones127@gmail.com>