register-runner: split the runner into two runners

In order to be able to run docker images inside docker, we mount the docker
socket inside the build container. This offer a security risk, as any CI job is
able interact with the docker engine the host.

To mitigate this, one runner is used to build docker images. This runner
should be limited to trusted projects.

The other runner can be shared, as it does not get the docker socket.
6 jobs for split-runner in 44 seconds (queued for 3 seconds)
Status Job ID Name Coverage
  Build
passed #9574
aarch64 ci-docker-image docker-alpine
build-aarch64

00:00:24

passed #9575
armv7 ci-docker-image docker-alpine
build-armv7

00:00:33

passed #9573
ppc64le ci-docker-image docker-alpine
build-ppc64le

00:00:31

passed #9570
s390x ci-docker-image docker-alpine
build-s390x

00:00:43

passed #9572
x86 ci-docker-image docker-alpine
build-x86

00:00:31

passed #9571
x86_64 ci-docker-image docker-alpine
build-x86_64

00:00:30