No, unfortunately you can’t, the image will be kept in your zpool until the last container that was created from it goes away.
That’s because ZFS’ model for dataset cloning keeps a reference to the entire source dataset, not to individual blocks within the dataset (as btrfs does for example). Meaning that even if your container no longer shares a single block with the image it was originally created from, you still cannot destroy that image without also causing your container to get deleted…