Revert "fix: source lib.sh in docker-buildx-push for tagging version"

This reverts commit 2f7a361.

Author: jsjoeio

ci/steps/docker-buildx-push.sh

@@ -3,9 +3,6 @@ set -euo pipefail
 
 main() {
   cd "$(dirname "$0")/../.."
-  # ci/lib.sh sets VERSION so it's available to ci/release-image/docker-bake.hcl
-  # to push the VERSION tag.
-  source ./ci/lib.sh
 
   # NOTE@jsjoeio - this script assumes that you've downloaded
   # the release-packages artifact to ./release-packages before