build ppc64el job failing on invalid image reference format

Pulling docker image registry.salsa.debian.org/salsa-ci-team/pipeline/ppc64le/base: ...
WARNING: Failed to pull image with policy "always": invalid reference format (manager.go:238:0s)
ERROR: Job failed: failed to pull image "registry.salsa.debian.org/salsa-ci-team/pipeline/ppc64le/base:" with specified policies [always]: invalid reference format (manager.go:238:0s)

It's because of the missing RELEASE variable. Related: #494 (closed) and #493

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information