Fix own mistake in rB7061d1e39fe
In my attempt to quickly address T92838, along with the original bug, I
made a nonsensical choice to use the limiter lock to guard the check
against the cache item itself. While harmless, it is not necessary and
semantically wrong / potentially confusing to future readers of the code.
Differential Revision: https://developer.blender.org/D13122
e8a8bb67fc