[C++] Add a method that accepts a Substrait plan and returns a RecordBatchReader

[asfimport]

This will shield implementations from having to deal with SinkNodeConsumer. The implementation should be pretty similar to the SinkNode that we have today for exec plans. We can use a PushGenerator to be our producer/consumer queue that the RecordBatchReader consumes. The Substrait sink consumer will then push into that PushGenerator. This method would fail if the plan has more than one top-level relation (e.g. more than one sink).

Reporter: Weston Pace / @westonpace

_{Note: This issue was originally created as ARROW-15849. Please see the migration documentation for further details.}

[asfimport]

Todd Farmer / @toddfarmer:
This issue was last updated over 90 days ago, which may be an indication it is no longer being actively worked. To better reflect the current state, the issue is being unassigned per project policy. Please feel free to re-take assignment of the issue if it is being actively worked, or if you plan to start that work soon.

[github-actions]

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