Add procps to :scm variants since it's fairly common in build systems
Add procps to :scm variants since it's fairly common in build systems

This needs to be explicit since stretch has managed to remove "procps" from minbase again! :tada:

infosiftr/buildpack-deps,docker-library/buildpack-deps,yyolk/buildpack-deps-graphicsmagick,vicamo/docker-buildpack-deps