bug#32942: nss-certs not deterministic

[Julien Lepiller]

While updating a profile, I found that nss-certs was not deterministic. 
From ludo:

$ wget -O - -q 
https://mirror.hydra.gnu.org/mbs5mavs3gi4y7xkywcwwjj9g3p1yjmv.narinfo | 
grep Hash
NarHash: sha256:101v69xp1qzw9v6pgmbhw7gfdaic8vvs4v5l567lx7f2mjp25rla
$ wget -O - -q 
https://berlin.guixsd.org/mbs5mavs3gi4y7xkywcwwjj9g3p1yjmv.narinfo | 
grep Hash
NarHash: sha256:08ziz714diyfq2klxy1nc0nhr5wa2vd356n9vizlq913a7an9a9s