ARROW-13772 binds quantile() to tdigest() which returns approximate quantiles and binds median() to approximate_median() which returns an approximate median. The bindings issue a warning saying that the median/quantile is approximate. Once ARROW-13309 is implemented, modify the binding to call Arrow functions that returns exact quantiles and medians, and remove the warnings.

We should keep the approximate quantile and median bindings but rename them.

When doing this, we should also modify the bindings to accept type and interpolation arguments like we do in the quantile.ArrowDatum method:

Reporter: Ian Cook / @ianmcook

Related issues:

• [R] Binding for median() and quantile() aggregation functions (relates to)
• [C++] Implement hash_aggregate exact quantile kernel (depends upon)

_{Note: This issue was originally created as ARROW-14021. Please see the migration documentation for further details.}