Improve the kernel locking logic in bootstrap scripts
We currently specify
4.15.0-1029 for kernel locking in our bootstrap script in production and staging. This causes problems when these builds no longer our available and also prevents us from taking minor updates on reboot.
If we consider locking we should probably only do this on the minor version. For now I have proposed that we remove the lock because it can cause instances to get in a bad state on boot.
kernel locks removed with https://ops.gitlab.net/gitlab-com/gitlab-com-infrastructure/merge_requests/808