arrow

GH-36096: [Python] Call __from_arrow__ in Array.to_pandas (#36314)

### Rationale for this change

Array.to_pandas should mimic ChunkedArray.to_pandas implementation. Notably, there is a missing call to `__from_arrow__` if the attribute exists.

### Are these changes tested?

Requires dev pandas. Can manually kick off integration tests to test with pandas nightly.

### Are there any user-facing changes?

No
* Closes: #36096

Authored-by: Dane Pitkin <dane@voltrondata.com>
Signed-off-by: Joris Van den Bossche <jorisvandenbossche@gmail.com>