This uses a new script and CircleCI job called "build-packages-dist"
which shims the new Bazel build to produce outputs matching the legacy
build. We'll use this to get AIO testing onto CircleCI as well.
We move the integration tests to a new circleCI job that depends on this
one, as well as the build publishing job.
Note that every PR will have a trivial green publishing status, because
we always create this job even for PRs. We'd rather not - see
https://discuss.circleci.com/t/workflows-pull-request-filter/14396/4
PR Close#23512
Alex Eagle