[Must Have] Summary

WT-6680 disabled code for history store verification.  This disabled code has remained in the sources for over a year. Since then the surrounding code has changed, and there have been tickets that needed to modify the disabled code (e.g., WT-7410).  

This disabled code should be removed.  If/when we need to add this functionality, we'll still be able to find the code in GitHub.

[Nice to have] Motivation

Does this affect any team outside of WT?

No

[Must Have] Acceptance Criteria (Definition of Done)

All #if 0 code labeled FIXME-WT-6682 or FIXME-WT-6263 is removed from WT source code

Testing

Standard PR and Evergreen tests pass.