Dockerfile.5.md stub
Properly formatted DCO:
Docker-DCO-1.1-Signed-off-by: Zac Dover <zdover@redhat.com> (github: zdover23)

Docker-DCO-1.1-Signed-off-by: Zac Dover <zdover@redhat.com> (github: )
Merge pull request #6039 from zdover23/26May_dockerfile

Dockerfile.5.md stub