Add ROS 2 Jazzy's planned Gazebo pairing

[azeey]

🎉 New feature

Summary

Documenting that we plan to pair ROS 2 Jazzy with Gazebo Harmonic.

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

Note to maintainers: Remember to use Squash-Merge and edit the commit message to match the pull request summary while retaining Signed-off-by messages.

[mabelzhang]

🎉