Set on_exit_shutdown argument for gz-sim ExecuteProcess

[andermi]

Signed-off-by: Michael Anderson [email protected]

🎉 New feature

Summary

Add launch argument to set gz-sim to be a required node: if argument on_exit_shutdown is True, set on_exit=Shutdown()

Test it

Make a launch file that includes gz_sim.launch.py as well as some other node. set gz_args to use --iterations 5000 and set on_exit_shutdown to True. When gz-sim exits, everything should quit.

Checklist

• Signed all commits for DCO
• Added tests
• Added example and/or tutorial
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
• While waiting for a review on your PR, please help review another open pull request to support the maintainers

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[andermi]

@mjcarroll It doesn't look like this PR made it into the humble branch

[mjcarroll]

I will backport to iron and humble, thanks.

[mjcarroll]

Humble: #451
Iron: #452