testdays is down again

[Kamil Paral]

> > ...
> > it's down :(
> 
> Seems to be working for me. Could you describe "down" a bit more? :)

I've found the issue. It's this:
http://en.wikipedia.org/wiki/HTTP_Strict_Transport_Security

testdays.qa.fedoraproject.org runs only on http, not https. But if you have visited https://qa.fedoraproject.org/ (e.g. https://qa.fedoraproject.org/blockerbugs/ ) recently, it sets this header for you:

  Strict-Transport-Security: max-age=15768000; includeSubDomains; preload

and then firefox automatically forces it for all subdomains, including testdays.qa.fedoraproject.org (for the next 6 months).

I guess the solution is to do some of these:
* set up testdays with https
* move it to a different domain
* don't include subdomains in the HSTS header

I have created a ticket in Phab:
https://phab.qadevel.cloud.fedoraproject.org/T434