The point is to reduce rebuild amount when updating cacert/nss,
though at *this* point it remains quite high - before & after:
Estimating rebuild amount by counting changed Hydra jobs (parallel=unset).
13109 x86_64-darwin
21567 x86_64-linux
Estimating rebuild amount by counting changed Hydra jobs (parallel=unset).
13109 x86_64-darwin
17141 x86_64-linux