Move the version-check for pruners to the pruner, which can return a [ErrNotImplemented] error to indicate they won't be run with the API version that's used. This helps separating concerns, and doesn't enforce knowledge about what's supported by each content-type onto the system prune command. [ErrNotImplemented]: https://pkg.go.dev/github.com/docker/docker@v28.3.3+incompatible/errdefs#ErrNotImplemented Signed-off-by: Sebastiaan van Stijn <github@gone.nl>