fix: use plugins-docker without version tag to match privileged images list

The Docker daemon was failing to start because the image
registry.sn48.zivili.ch/library/plugins-docker:24.0.0 wasn't in the
DRONE_RUNNER_PRIVILEGED_IMAGES list. Changed to use the image without
version tag to match the privileged configuration.

.drone.yml

@@ -21,8 +21,7 @@ steps:
       - tag
 
 - name: publish
-  # image: plugins/docker
-  image: registry.sn48.zivili.ch/library/plugins-docker:24.0.0
+  image: registry.sn48.zivili.ch/library/plugins-docker
   # CRITICAL: Enable BuildKit at step environment level (not build_args!)
   environment:
     DOCKER_BUILDKIT: "1"