community/gnome-software: use external appstream data

We stopped updating alpinelinux-appstream-data, so fetch external
appstream data here instead
7 jobs for !12654 with 3.12-gnome-software in 2 minutes and 59 seconds (queued for 2 seconds)
latest detached
Status Job ID Name Coverage
  Lint
passed #210855
x86_64 docker-alpine
lint

00:00:26

 
  Build
passed #210860
aarch64 ci-build docker-alpine
build-aarch64

00:01:52

passed #210861
armv7 ci-build docker-alpine
build-armv7

00:02:00

passed #210859
ppc64le ci-build docker-alpine
build-ppc64le

00:02:29

passed #210858
s390x ci-build docker-alpine
build-s390x

00:00:28

passed #210857
x86 ci-build docker-alpine
build-x86

00:01:23

passed #210856
x86_64 ci-build docker-alpine
build-x86_64

00:01:22