Change a .forEach() loop to a for...of loop

Tucker McKnight <tmcknight@instructure.com> | Sat Sep 26 2026

Change a .forEach() loop to a for...of loop

This has given an absolutely ginormous performance boost. Literally
solved performance woes on all but the largest git repos with 50,000+
commits.

Also removed an unnecessary .join() call, where the string was then
just being .split() again right afterwards.

Also created a constant for how many commits should be read at once.
And changed it from 10 to 100. Let's make this customizable in the
future.