Test linux-ppc64le and linux-aarch64 installers

[chrisburr]

It would be possible to test the linux-ppc64le and linux-aarch64 installers using QEMU in CI so we probably should. 😄

[chrisburr]

# I'm not sure exactly how the GitHub actions runners are configured but this should work
curl -LO https://github.com/multiarch/qemu-user-static/releases/latest/download/qemu-aarch64-static
chmod +x qemu-aarch64-static
docker run --rm --privileged multiarch/qemu-user-static:register --reset --credential yes
docker run -v $PWD/qemu-aarch64-static:/usr/bin/qemu-aarch64-static:ro --rm -it quay.io/centos/centos:stream9 bash

# From inside the container
$ curl -LO https://github.com/DIRACGrid/DIRACOS2/releases/latest/download/DIRACOS-Linux-aarch64.sh
$ bash DIRACOS-Linux-aarch64.sh
$ source /diracos/diracosrc
$ pip install DIRAC