UCP docker images are not being tagged with a version

[craiganderson]

One of the standards from OSH that should be adopted for UCP is non-reusable version tags for images. Presently, only "latest" and "master" are available, whereas other OSH and upstream components are identified with an explicit version tag that uniquely identifies an image (e.g., v1.7.5) and isn't re-used for any subsequent image updates.

This provides a cleaner, human-readable way to uniquely reference images versus a SHA256.

@alanmeadows
@slfletch
@bryan-strassner