Hello, I'm responsible for upgrading the installer so that it works on Debian 10.
Yesterday, I fixed the problem you had in apache: https://lab.nexedi.com/nexedi/slapos/commit/e018d9df44243cf35340db0b0d1b88eafaa2e0a3
Today, I released a new version and push it into the playbook so you can already try the new version (see my latests commits in the installer script: https://lab.nexedi.com/nexedi/slapos.package/commits/master)
I'm currently building everything and pushing it into our software cache. Once this is done, the test should work again.
Sorry for the inconvenience, we started to port everything to Debian 10 quite lately.