Make GitHub releases in addition to GitLab releases

I've found GitLab Releases to be significantly slower than GitHub Releases for downloading assets. I did some testing to verify everything, and this is what I found (using curl on the arch.tar.gz images):

GitLab (almost 6 minutes):

root@2269f44a3f54:~# curl 'https://gitlab.com/api/v4/projects/43000137/packages/generic/fim/continuous/arch.tar.xz' > arch.tar.xz
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100  409M  100  409M    0     0  1176k      0  0:05:56  0:05:56 --:--:-- 1497k

GitHub (almost 50 seconds):

root@2269f44a3f54:~# curl 'https://github.com/hwittenborn/release-testing/releases/download/0.0.0/alpine.tar.xz' -L > arch.tar.xz.2
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
  0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0
100 54.1M  100 54.1M    0     0  1143k      0  0:00:48  0:00:48 --:--:-- 1645k

It would be great if I could use GitHub Releases, as it would make my CI runs significantly quicker.

I don't know how I overlooked it, it looks like I accidentally used the alpine image for my testing on GitHub Releases though. Looking at things like the average download speeds it looks like they're pretty identical, I'll go ahead and get this closed.

Sorry about that!