Remove comment suggesting reading Subversion logs for documentation

Summary: I can't imagine how comments could have a significant impact in run time, even in Bash, but the code seems to be commented nonetheless, including TODO comments which may be better suited for a Phabricator task instead, so I think this comment is outdated.

Test Plan: No code affected

Reviewers: ltoscano, aacid

Reviewed By: aacid

Differential Revision: https://phabricator.kde.org/D24410