Denying the use of racially biased facial recognition software is a much clearer example where the risks are lower and the impact much, much greater.
It's much less clear that a source code repository is the fulcrum that enables 40 children to be jammed into a room without hygiene. Maybe if you worked for a critical supplier for ICE you could have an impact (which I would much encourage).
I fundamentally disagree with this. Your argument is akin to stating that there should never be any casualties in a war. There is no way to effectively win a war without sometimes sending some troops into situations where you know they will die.
Compared to soldiers who knowingly lay down their lives in losing battles to help win the war, choosing a moral course of action that merely ends a company seems like a pretty cheap sacrifice.