Remove build-ci Workflow

[CodeGat]

The second iteration of build-ci will not have hooks in the state of spack-packages. Similar to build-cd, it will be a responsibility of the model (component) developer to check and choose the version of spack-packages that is built.

The reason for the removal of this workflow is that we no longer will associate a spack base image with a particular version of spack-packages, since it is trivial to change it through git checkout ....