Naive pub/sub example should be in ros2 directory

[griswaldbrooks]

Need

In order to see a naive example of pub/sub testing in ros2
As a developer
I want to have a naive pub/sub package

Acceptance Criteria

Scenario: ros2 pub/sub node should exist for testing
GIVEN we want to show testing pub/sub in ros2
WHEN writing those gtests
THEN a naive publisher/subscriber package should be available

Tasks

• Create ros2 naive package
• Port Incrementer class into package
• Write readme on how to use on cli

Notes

I'm open to calling this something other than naive in case that is diminutive.

References:
https://github.com/PickNikRobotics/ros_testing_templates/tree/main/ros1/naive