Hoot Release Fix & CircleCI Image Updates

[jbronn]

• Respect HOOT_RELEASE environment variable so it's possible to create an iteration release, e.g. for 0.2.72-2:

  HOOT_RELEASE=2 HOOT_VERSION_GEN=0.2.72 make rpm

• Update CircleCI images to latest versions.
• Updates to pgdg-repo.sh (check metadata signatures, support testing repository) and geoint-deps.sh (EL9, make repo name cache friendly).
• Minor cleanup of Dockerfile.rpmbuild-pgdg