Update .gitlab-ci.yml

1 job for master in 1 minute and 12 seconds (queued for 4 seconds)
Status Job ID Name Coverage
  Test
failed #72
pages

00:01:12

 
Name Stage Failure
failed
pages Test
Removing public/
HEAD is now at 85ef9eb Update Doxyfile
From https://git.itsblue.de/Fenoglio/coderacer
85ef9eb..b3bacc2 master -> origin/master
Checking out b3bacc26 as master...
Skipping Git submodules setup
$ apk update
/bin/bash: line 67: apk: command not found
ERROR: Job failed: exit code 1