Rename project name from ros2_diag_tree to ros2_medkit

[bburda]

Pull Request

Description

Rename project from ros2_diag_tree to ros2_medkit

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update

Related issues

closes #9

How has this been tested?

colcon build and colcon test

Checklist

• My code follows the project's coding style
• I ran colcon build and the build succeeds without warnings
• I ran colcon test and all tests pass locally
• I added/updated tests where applicable
• I updated documentation where applicable
• My commit messages are clear and descriptive

Additional notes for reviewers