For a university course I have developed a software application in a group of 12 students. So far we have been developing without a license (in a private repository), but now that the course is over we would like to continue working on the project under the AGPL v3 license. Since we are about to open a new (public) repository soon this seems like the right time to add it.
What steps do we need to take in order to 'change' the license of our code base? I could imagine that simply adding the license to the new repository is not enough, since this action can be done by just one team member.