Update control.tf

[bmagyar]

Karsten hasn't been active for a few years now, Christoph is eager to learn the ropes

[christophfroehlich]

@nuclearsandwich thanks for merging, but I still don't have access to any of the release repositories.
bloom-release fails, and also a manual checkout fails:

$ git push --set-upstream origin test_access --dry-run
remote: Permission to ros2-gbp/control_toolbox-release.git denied to christophfroehlich.
fatal: unable to access 'https://github.com/ros2-gbp/control_toolbox-release.git/': The requested URL returned error: 403

Is there anything missing from our side, or have the gbp access rights to be updated by anyone after merging this PR?

[nuclearsandwich]

This change has been deployed!

[christophfroehlich]

Thanks, now I was able to push the release!