pkgpush: use head_bucket() instead of get_bucket_location() to get region (#2844)
pkgpush: use head_bucket() instead of get_bucket_location() to get region (#2844)

Related to https://github.com/quiltdata/enterprise/pull/388
quiltdata/quilt,quiltdata/quilt,quiltdata/quilt,quiltdata/quilt,quiltdata/quilt