After each deployment in sandbox or production, move the artifacts from
the corresponding release to a well-known location so that they can be
mapped to Kokoro in presubmit tests. The Kokoro-mapping does not need
public access to the GCS bucket.
The artifacts include the postgresql schema jar, the nomulus release
jar, and the uber jar of the nomulus schema integration test classes.
Every jar name consists of a fixed prefix and the environment. Each jar
of a new deployment overrides the previous copy.
