arrow

GH-36045:[Python] Improve usability of pc.map_lookup / MapLookupOptions (#36387)

### Rationale for this change
This PR is for #36045, which aims to improve usability of pc.map_lookup / MapLookupOptions  

### What changes are included in this PR?
For `query_key` which is not a subclass of `pyarrow.lib.Scalar`, we convert it to `scalar`

### Are these changes tested?

Yes, add one test in tests/test_compute.py::test_map_lookup
* Closes: #36045

Lead-authored-by: Junming Chen <junming.chen.r@outlook.com>
Co-authored-by: Joris Van den Bossche <jorisvandenbossche@gmail.com>
Signed-off-by: Joris Van den Bossche <jorisvandenbossche@gmail.com>