Update the containerd binary that's used in CI and for the static packages.

- release notes: https://github.com/containerd/containerd/releases/tag/v1.7.18
- full diff: containerd/containerd@v1.7.17...v1.7.18

Welcome to the v1.7.18 release of containerd!

The eighteenth patch release for containerd 1.7 contains various updates along
with an updated version of Go. Go 1.22.4 and 1.21.11 include a fix for a symlink
time of check to time of use race condition during directory removal.

Highlights

- Update Go version to 1.21.11
- Remove uses of platforms.Platform alias
- Migrate log imports to github.com/containerd/log
- Migrate errdefs package to github.com/containerd/errdefs
- Fix usage of "unknown" platform

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
(cherry picked from commit 5318c38)
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>