Fixes submodule staging to preserve symlink
Fixes submodule staging to preserve symlink

found to be disastrous for mindbender (Thanks to @daniter-cu)

HazyResearch/deepdive,shahin/deepdive,HazyResearch/deepdive,sky-xu/deepdive,shahin/deepdive,HazyResearch/deepdive,HazyResearch/deepdive,sky-xu/deepdive