Add grouping aggregate function once implemented upstream

[timsaucer]

Is your feature request related to a problem or challenge? Please describe what you are trying to do.
Once this upstream issue is resolved, add the appropriate functions and unit tests.

apache/datafusion#12377

Additional context
At the time of this writing the grouping function is exposed to end users, but a current PR I am working on will remove it since it is not actually implemented in datafusion and will only lead to confusion of users.