Broken Ceph Storage documentation links

[stefanoghinelli]

Describe the bug

In the documentation page deploy_quay_ha.html, the links to Ceph Storage installation guides are broken.
They use the version 3.15, and the URLs seem to be outdated.

To Reproduce

1. Go to https://docs.projectquay.io/deploy_quay_ha.html#_set_up_ceph
2. Click on links like: Installing Red Hat Ceph Storage on Red Hat Enterprise Linux
3. The page does not exist.

Thanks