Fix sample fstab file in GitLab HA docs
The nobootwait option is no longer a valid option in Ubuntu 16.04. Use nofail instead:
https://askubuntu.com/questions/786928/ubuntu-16-04-fstab-fails-with-nobootwait
The nobootwait option is no longer a valid option in Ubuntu 16.04. Use nofail instead:
https://askubuntu.com/questions/786928/ubuntu-16-04-fstab-fails-with-nobootwait