Fix plugin crash and update sim_plugins.gzlaunch

[iche033]

🦟 Bug fix

Summary

• Fixes crash when a plugin fails to load.
  • When joystick plugin fails to load (because there's no joystick device) the plugin gets deleted when it goes out of scope. This led to a crash. The workaround is to store the plugin and let gz launch destroy them when it exists.
• Updated sim_plugins.gzlaunch to use the latest gui plugins since GzScene3D is no longer available. There's probably a smarter way to include all plugins from gz sim's gui.config. This is more of a patch to get things working.

Known issue - gz launch now spins up gz sim and gui correctly but there is still an issue shutting down cleanly with Ctrl + C. I had to force kill the gz-launch process.

Checklist

• Signed all commits for DCO
• Added tests
• 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)
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