Remove major version from package name

[scpeters]

🎉 New feature

Part of gazebo-tooling/release-tools#1244

Summary

This removes the major version from the package
name in the following places:

• cmake project name and corresponding find_package calls in examples and tutorials
• package.xml name

Test it

See companion pull requests for a colcon CI job testing all branches simultaneously

• Find gz-gui without major version gz-launch#293 (comment): https://build.osrfoundation.org/job/ci__colcon_any-manual_ubuntu_noble_amd64/24/

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.

[scpeters]

trying a nightly build:

• https://build.osrfoundation.org/job/gz-gui10-debbuilder/140/

[j-rivero]

trying a nightly build:

great !