Index tool when verifying from index to data doesn't correctly split page into tasks

When running index tool with index table as source, it splits a page into tasks when the page size is greater than the configured task size (default 2048) and runs each task in parallel. Each task is assigned a set of data row keys but the index mutation map is not split according to the data row keys assigned to a particular task. As a result, the tool reports wrong results because the index mutation map is per page but the set of data row keys is per task.