Prefetch vmlinuz and initrd on sync
KS repos are usually marked on demand. This means "images/pxeboot/vmlinuz" and "images/pxeboot/initrd" are likely to be broken symlinks that are lazily loaded and pulled in only when needed.
During provisioning Smart Proxy tries to fetch these files from the master server to copy em to the tftp server. The lazy loading factor may result in timeout issues for the smart proxy causing the action to fail.
We should "prefetch" these files during repo syncs on both the master and proxies to avoid potential timeout issues.
Fixes #22318 - Fetches pxe files on sync
This commit adds an extra step to the repository "sync" plan to directly
fetch initrd/vmlinuz in the case of a bootable distribution for an
OnDemand repo. This eager fetching is done to mitigate future timeout
issues when the smart proxy requests these 2 files on provisioning.