Improve error message when aggregate function is applied to a nun-numeric column

Pinot currently supports aggregation functions for e.g max() on numeric values only, however if you run a query where a non-numeric column is passed as a value then error message generated is really vague and totally misleading:

We should have a explicit error message indicating lack of support for non-numeric data and the offending function used in the query.

cc @mayankshriv @kishoreg

Start by reproducing a Pinot query that applies max() to a non-numeric column, then trace the aggregate-function error handling. Done means the error explicitly states that non-numeric data is unsupported and identifies the offending aggregation function.

Written by the indexing model from the issue text.