Remove golang.org/x/exp dependency when Go 1.23 is released

[meling]

In cmd/latencygen/latency_gen.go:32 we can replace these two lines:

keys := maps.Keys(allToAllMatrix)
sort.Strings(keys)

With this line:

keys := slices.Sorted(maps.Keys(allToAllMatrix))

When Go 1.23 is released with support for rangefunc. See golang/go:#61538 for additional context and golang/go:#61900 for the accepted proposal.

Similar updates needs to be done in crypto/cache.go and twins/network.go.