elements/components/nettle.bst: update to 3.5.1

According to upstream changelog, 'nettle-stdint.h' header was removed
thus we don't need to move it around anymore.
https://git.lysator.liu.se/nettle/nettle/blob/nettle_3.5.1_release_20190627/NEWS#L85
10 jobs for EmersonBernier/update_components_v3 in 660 minutes and 56 seconds (queued for 5 seconds)
Status Job ID Name Coverage
  Flatpak
passed #253621151
aarch64
app_aarch64

10:22:37

passed #253621152
armhf
app_arm

03:59:26

passed #253621146
cache_i686 x86_64
app_i686

04:25:13

passed #253621153
ppc64le allowed to fail
app_powerpc64le

03:58:43

passed #253621144
cache_x86_64 x86_64
app_x86_64

04:23:04

 
  Vm
manual #253621158
aarch64 allowed to fail manual
minimal_systemd_vm_aarch64
passed #253621159
armhf
minimal_systemd_vm_arm

00:07:37

passed #253621157
cache_i686 x86_64
minimal_systemd_vm_i686

00:38:18

manual #253621160
ppc64le allowed to fail manual
minimal_systemd_vm_powerpc64le
passed #253621155
cache_x86_64 x86_64
minimal_systemd_vm_x86_64

00:32:11