[docker-in-docker] - Fixing issue with containerd

[Kaniska244]

Summary

This PR fixes a docker-in-docker issue where containerd can fail when the dev container root filesystem is itself mounted as overlayfs.

The fix adds a dedicated persisted volume for /var/lib/containerd, ensuring that containerd snapshotter state is stored on non-overlay storage. This prevents overlay-on-overlay mount failures such as invalid argument during image pull or container startup.
Fixes this follow-up issue

Changes included

• Add persisted volume mount for:
  • dind-var-lib-containerd-${devcontainerId} → /var/lib/containerd
• Bump docker-in-docker feature version from 3.0.0 to 3.0.1
• Document persisted Docker/containerd state and the overlayfs limitation in src/docker-in-docker/NOTES.md
• Add regression test:
  • test/docker-in-docker/overlayfs_containerd_root.sh
• Add test scenario:
  • overlayfs_containerd_root
• Update workflow coverage to use mcr.microsoft.com/devcontainers/base:noble where needed
• Extend PR test matrix to cover docker-in-docker on Ubuntu-based images

Why this fix is needed

When /var/lib/containerd lives on an overlay-backed root filesystem, the standalone containerd started by this feature may attempt to place overlayfs snapshotter data on top of another overlay mount. In affected environments, this can cause container/image operations to fail with errors like:

• failed to mount ... invalid argument

Mounting /var/lib/containerd on its own named volume avoids that storage layout and makes the feature work reliably in containerd-backed and overlayfs-based environments.

Validation

This PR adds regression coverage to verify that:

• the root filesystem is overlay
• /var/lib/containerd is not mounted as overlay
• /var/lib/docker is not mounted as overlay
• docker run --rm hello-world succeeds
• the containerd snapshotter code path is actually exercised

Notes

The new persisted volumes are scoped by ${devcontainerId}, so each dev container gets isolated state while preserving images/snapshots across rebuilds. These volumes are not automatically removed when the dev container is deleted.