Organization of pull request validation on git

As part of a project for the university, we have to work on a project in C with 6 students. It is required that we use the gitLab platform.

The question that I find a little tricky is the following, how are we going to decide who can validate the pull requests knowing that we have no particular skills that distinguish us from each other and that we want a fair and democratic process?

I thought of several ways and the one that stood out in my opinion was that we could all validate the pull requests and that it would be confirmed as soon as any two people validated.

This seems more flexible and simple to me than requiring the agreement of 6 people or rotating between people who can validate. That said, as I have not yet been able to put the idea into practice, I appeal to your experience, what do you think? Would you suggest anything else?