Otherwise it creates absurd situation in which highly expensive institution is demanding that part of teaching is done by third parties for free.
That said, I would love if the professor would reach out so I could recommend specific issues and let them know whether I'll be particularly available for more in depth PR mentoring this semester.
It does seem like they're accounting for the burden put on maintainers as well:
> Getting a contribution accepted is not a prerequisite for passing the assignment
> a small-scale contribution is the only realistic goal. The key to making the course's assignment work, is to have what are, on first sight, very low ambitions for the students' contributions.