[Podman] Changing shell for RUNs in Containerfile without SHELL instruction

Hi folks, Could you please tell me is there an easy way how to use something like SHELL instruction in Containerfile? OCI specs don't support SHELL so by default "podman build" requires --format docker but I would prefer to avoid it an use "pure" Podman / OCI. I would like to use something like: SHELL ["/bin/bash", "-c"] So I can use Bashisms like for example: RUN tee file <<< 'hello' instead of: RUN bash -c "tee file <<< 'hello'" (I know I can echo hello | tee file, this is just a stupid example of Bashism. I was thinking changing ENTRYPOINT at the beginning of Container file to ENTRYPOINT ["/bin/bash", "-c"] But that doesn't work... Any suggestions are most welcomed ;-). (just please don't suggest not using Bashisms, I like them! ;-)) Thank you. Hans