Bump skopeo/stable from v1.15.2 to v1.16.0 in /tests in the docker-te…

…sts group (#6242)

Bump skopeo/stable in /tests in the docker-tests group

Bumps the docker-tests group in /tests with 1 update: [skopeo/stable](https://github.com/containers/image_build).


Updates `skopeo/stable` from v1.15.2 to v1.16.0
- [Commits](https://github.com/containers/image_build/commits)

---
updated-dependencies:
- dependency-name: skopeo/stable
  dependency-type: direct:production
  dependency-group: docker-tests
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

tests/Dockerfile

@@ -3,7 +3,7 @@
 FROM kindest/node:v1.31.0@sha256:53df588e04085fd41ae12de0c3fe4c72f7013bba32a20e7325357a1ac94ba865
 
 # this is here so we can grab the latest version of skopeo and have dependabot keep it up to date
-FROM quay.io/skopeo/stable:v1.15.2
+FROM quay.io/skopeo/stable:v1.16.0
 
 FROM python:3.12@sha256:e3d5b6f95ce66923b5e48a06ee5755abb097de96a8617c3f2f7d431d48e63d35