edit .gitlabci file

1 job for gitlab in 1 minute and 13 seconds (queued for 7 seconds)
Status Job ID Name Coverage
  Test
failed #2947942
jobs

00:01:13

 
Name Stage Failure
failed
jobs Test There is an unknown failure, please try again
 93800K .......... .......... ....                            100% 72.2M=3.6s

2016-08-09 14:44:59 (25.4 MB/s) - ‘arduino-1.6.9-linux64.tar.xz’ saved [96075820/96075820]

$ tar xf arduino-1.6.9-linux64.tar.xz
$ /usr/local/bin/start-xvfb
/bin/bash: line 48: /usr/local/bin/start-xvfb: No such file or directory

ERROR: Build failed: exit code 1