[ros] Provide exact version numbers to ensure rebuilds #112
Description
Context in docker-library/official-images#3890.
TL;DR the docker images don't get rebuilt as the version of the metapackages never changes. We need a way to get them re-triggered.
Possible solution: provide exact version numbers for the packages in docker files so that the docker cache is invalidated. One con is that these version differ for each platform / arch so we need to find a way to conditionally set the right version for each arch without duplicating dockerfiles.