Add --force-rm to docker run

Docker-DCO-1.1-Signed-off-by: Adrien Folie <folie.adrien@gmail.com> (github: folieadrien)

Docker-DCO-1.1-Signed-off-by: Victor Vieux <vieux@docker.com> (github: vieux)
simplify

Docker-DCO-1.1-Signed-off-by: Victor Vieux <vieux@docker.com> (github: vieux)