Publish OCI images with a revision tag

[Valentin Viennot]

Each newly built container image of an application (repository) should be associated with a unique and incremental build number, a revision (as in Snap revisions). This revision number should be controlled by the build system (ie; Launchpad itself), and published along the newly built image as its first “tag”. As a result, each image coming out of Launchpad OCI build system would get two default tags: first a revision (eg; “8.0-20.04_rev123”), and second a default channel tag (eg; “8.0-20.04_edge”). Any further move between channels will happen through a separate “promotion process” as it is already the case today.