Merge branch 'gitlab-runner-community' into 'master'

dockerfile: install gitlab-runner-helper from community

See merge request !3
3 jobs for enable-x86 in 27 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Build
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s390x docker-alpine
build-s390x

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x86 docker-alpine
build-x86

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passed #443
x86_64 docker-alpine
build-x86_64

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