Update CMakeLists.txt

[mosfet80]

fix cmake <3.10 deprecation
allign ros2 cxx requiremant = cxx17

Contributions via pull requests are much appreciated. Before sending us a pull request, please ensure that:

1. Limited scope. Your PR should do one thing or one set of things. Avoid adding “random fixes” to PRs. Put those on separate PRs.
2. Give your PR a descriptive title. Add a short summary, if required.
3. Make sure the pipeline is green.
4. Don’t be afraid to request reviews from maintainers.
5. New code = new tests. If you are adding new functionality, always make sure to add some tests exercising the code and serving as live documentation of your original intention.

To send us a pull request, please:

• Fork the repository.
• Modify the source; please focus on the specific change you are contributing. If you also reformat all the code, it will be hard for us to focus on your change.
• Ensure local tests pass. (colcon test and pre-commit run (requires you to install pre-commit by pip3 install pre-commit)
• Commit to your fork using clear commit messages.
• Send a pull request, answering any default questions in the pull request interface.
• Pay attention to any automated CI failures reported in the pull request, and stay involved in the conversation.

[christophfroehlich]

I fixed the CXX standard globally in ros-controls/ros2_control_cmake#7, but do we need that at all in a message-only package like control_msgs?

Regarding cmake version, let's wait for the result in ros2/ros2_documentation#5639, because the docs are not consistent here:

https://docs.ros.org/en/rolling/How-To-Guides/Ament-CMake-Documentation.html
https://docs.ros.org/en/rolling/Tutorials/Beginner-Client-Libraries/Writing-A-Simple-Cpp-Publisher-And-Subscriber.html