These are primarily simplification and lint mistakes. However, minor
fixes are also included and tests added where appropriate.
PiperOrigin-RevId: 351425971
This change adds a layer of abstraction around the internal Docker APIs,
and eliminates all direct dependencies on Dockerfiles in the infrastructure.
A subsequent change will automated the generation of local images (with
efficient caching). Note that this change drops the use of bazel container
rules, as that experiment does not seem to be viable.
PiperOrigin-RevId: 308095430