Tools: Add pre-commit hook to check copyright in ros2 files

[cclauss]

Add a local pre-commit hook to verify the copyright notice is in all Python files in Tools/ros2.

% pre-commit run check-copyright --verbose --all-files

Make exceptions for:

Tools/gittools/pre_commit_copyright.py \
    --ignore=Tools/ros2/ardupilot_dds_tests/setup.py \
    --ignore=Tools/ros2/ardupilot_dds_tests/test/test_pep257.py \
    --ignore=Tools/ros2/ardupilot_dds_tests/test/test_copyright.py

How was this tested?

% Tools/gittools/pre_commit_copyright.py

Usage: python pre_commit_copyright.py file_path [...]

% Tools/gittools/pre_commit_copyright.py README.md

Copyright not found in: README.md

% Tools/gittools/pre_commit_copyright.py README.md COPYING.txt

Copyright not found in: COPYING.txt, README.md

% Tools/gittools/pre_commit_copyright.py Tools/ros2/ardupilot_sitl/launch/sitl.launch.py

<Nothing because this file has the copyright notice.>

% pre-commit run check-copyright --verbose --all-files

Check copyright notice in files..........................................Passed
- hook id: check-copyright
- duration: 0.08s

Edit Tools/gittools/pre_commit_copyright.py and add a Z to the front of each of the exclude_file_paths.
% pre-commit run check-copyright --verbose --all-files

Check copyright notice in files..........................................Failed
- hook id: check-copyright
- duration: 0.07s
- exit code: 1

Copyright not found in: Tools/ros2/ardupilot_dds_tests/setup.py
Copyright not found in: Tools/ros2/ardupilot_dds_tests/test/test_pep257.py
Copyright not found in: Tools/ros2/ardupilot_dds_tests/test/test_copyright.py

Edit Tools/gittools/pre_commit_copyright.py to remove those Z's.

[Ryanf55]

This is a nice addition for something that has so far been a manual verification.