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GH-35125: [C++][Acero] Add a self-defined io-executor in QueryOptions (#35464)



### Rationale for this change

Support a custom io-executor in Acero QueryOptions.

### What changes are included in this PR?

Allow user to define a customed io-executor.

### Are these changes tested?

Currently not

### Are there any user-facing changes?

User can specify an io-executor

* Closes: #35125

Authored-by: mwish <maplewish117@gmail.com>
Signed-off-by: Weston Pace <weston.pace@gmail.com>