[th/code-format-container] clang-format: rework "nm-code-format-container.sh" script

Instead of doing the broken podman run and podman start approach, build an image ("nm-code-format:f38"), cache it, and use it to run "nm-code-format.sh" via podman run. We should build and keep a container image, not a container.

The benefit is that this allows to hand over the command line arguments to "nm-code-format.sh". In particular the "-u" and "-F" options, which are life savers.

This means,

$ contrib/scripts/nm-code-format-container.sh -u

works.

Try also

$ contrib/scripts/nm-code-format-container.sh -h

which tells you that you are running inside the container, and how to delete/renew the container image.