Currently, the stat that gets incremented when a v2 bucket encounters an out of order insert and has to be converted to a v3 bucket is 'numBucketsPromoted'. The use of the word promote might unintentionally give off the impression that this is a good thing (in fact, no longer being able to guarantee sortedness would be more of a negative change if anything, or at best neutral). This ticket would change the metric name to be less misleading (numCompressedBucketsConvertedToUnsorted)