Button: "Download tarball" only downloads newest version although specifying older one

When download an old version from a collection (e.g ansible.tower 3.7.0) from cloud.redhat.com or a private AH with the "Download tarball" button, only download the latest version.

Steps to Reproduce:
1. Login in cloud.redhat.com or private AH.
2. Download old version collection with the "Download tarball"  (e.g ansible.tower 3.7.0)

Actual results:
Download the latest version

Expected results:
Download the version required.