ci: upgrade containerd version in integration tests

[nayuta723]

Overview

The current containerd integration test job in CI uses a pinned version (v1.7.11) and has tests being silently skipped due to missing dependencies (e.g., CRIU not installed). This makes it hard to understand the actual test coverage.

This issue tracks the work to upgrade containerd in CI and make skipped tests explicit.

Steps

• Audit the containerd integration tests in CI to identify all tests that are currently being silently skipped
  • Related to CheckpointTest: ci: install CRIU in containerd integration tests and skip checkpoint tests #3475
• Upgrade the containerd version used in the CI integration test job
• For tests that youki does not yet support, add explicit -skip entries with comments explaining why they are excluded

Motivation

Silent skips in CI are easy to overlook and can lead to reduced test coverage going unnoticed. By making all skips explicit, it becomes clear which tests are intentionally excluded and why, making the CI results more trustworthy and easier to maintain.