When pruning partitions for a query plan, a message is logged indicating what how many partitions were selected based on predicate criteria, and what percent were pruned.

The current release erroneously uses `1 - total/selected` to compute this quantity, leading to nonsense messages like "pruned -1000% partitions". The fix is simple and obvious.

Author: Steve Lindemann <steve.lindemann@engineersgatelp.com>

Closes #7227 from srlindemann/master and squashes the following commits:

c788061 [Steve Lindemann] fix percentPruned log message