[C++] ARROW_PYTHON misses ARROW_ACERO dependency

[kou]

Describe the bug, including details regarding any error messages, version, and platform.

PyArrow wants it.

Component(s)

C++

[kou]

This is needless because ARROW_PYTHON depends on ARROW_ACERO implicitly: ARROW_PYTHON -> ARROW_DATASET -> ARROW_ACERO