testing/screenfetch: remove

There is neofetch which is more recent, support more features, has
better support and doesn't have issues like #11802

See: https://github.com/dylanaraps/neofetch/wiki/Neofetch-vs-Screenfetch/a9c174beecfa9a4e547a9dfd7fac0491e35de84b
7 jobs for !11009 with screenfetch in 1 minute and 10 seconds
detached
Status Job ID Name Coverage
  Lint
passed #178529
x86_64 docker-alpine
lint

00:00:23

 
  Build
passed #178534
aarch64 ci-build docker-alpine
build-aarch64

00:00:24

passed #178535
armv7 ci-build docker-alpine
build-armv7

00:00:28

passed #178533
ppc64le ci-build docker-alpine
build-ppc64le

00:00:45

passed #178532
s390x ci-build docker-alpine
build-s390x

00:00:19

passed #178531
x86 ci-build docker-alpine
build-x86

00:00:20

passed #178530
x86_64 ci-build docker-alpine
build-x86_64

00:00:24