- [x] Have you followed the guidelines for contributing? - [x] Have you signed the [CLA](http://www.ubuntu.com/legal/contributors/)? - [x] Have you successfully run `make lint && make test`? --- This PR adds Podman as an alternative to Docker when running rocks. --- See [built docs](https://canonical-ubuntu-documentation-library--864.com.readthedocs.build/rockcraft/en/864/tutorial/hello-world/#run-the-rock)