[Feature Request] Use landlock for sandboxing VM process

# Feature Request

Jailer could use [Landlock](https://landlock.io) to confine guest VM's processes further, restricting fine-grained file system access than what current chroot can provide. This would be a defense in depth mechanism if the VM escape or host compromise is attempted.

## Describe the desired solution

Landlock would allows apps inside guest VM to have nested sandboxing for file paths.

## Describe possible alternatives

Keep using existing chroot trick. But that's not ideal.

## Additional context

I'm working on an OS similar to QubesOS where every app is a microVM.

## Checks

- [x] Have you searched the Firecracker Issues database for similar requests?
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