don't suppress unpublished examples (#2855)

## Motivation and Context
The publish tool doesn't consider unpublished crates when computing the
version tree for publish. This causes errors for examples that use
shared crates.

## Description
This adds support for considering unpublished crates when publishing. It
allows unpublished crates to have unpublished dependencies but published
crates can only have unpublished crates as dev dependencies.

## Testing
- [x] build these exact changes into the docker image and test

## Checklist
<!--- If a checkbox below is not applicable, then please DELETE it
rather than leaving it unchecked -->
- [ ] I have updated `CHANGELOG.next.toml` if I made changes to the
smithy-rs codegen or runtime crates
- [ ] I have updated `CHANGELOG.next.toml` if I made changes to the AWS
SDK, generated SDK code, or SDK runtime crates

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