simplify the docker run command and base container

[sheldonhull]

Would you be up for a PR for a chainguard based image that should simplify the docker run option? They are well maintained secured images and very tiny.

docker run \
    --mount type=bind,source=$PWD,target=/src \
    -w /src \
    -it \
    --user $(id -u ${USER}):$(id -g ${USER}) \
    ghcr.io/miniscruff/changie \
    new

docker run -it --rm $(PWD):/app ghcr.io/miniscruff/changie new

It's still really small, but I've moved away from scratch to the chainguard nonroot static binary image and it's a great default to use, and has default nonroot user and such set. Should trim down the size of run instructions.

[miniscruff]

I could maybe add an extra docker image in goreleaser but I don't think modifying the original will be a good idea. Not sure of ghcr.io/miniscruff/changie:chainguard is a good idea either though. Tbh the docker image was more of an after thought.

[miniscruff]

Kinda forgot about this but I think realistically its better to leave it as is considering docker is probably the least common method of using changie as it is.