Assignmentanswers in Teams can be read by everyone

It turns out that the Excel-file that is generated for me to view the results of a Forms-test, given as an assignment in Teams, is placed in the Teams-library where Teams-members are granted editing rights by default. This, not only makes it possible for every Team-member, my students, to see everyone's result, but also to edit the answers. I know it is possible to alter the rights given to this library, but I don't like the idea of instructing every teacher in our school to do this. This Excel-file should NOT be placed in this library, but rather in my personal OneDrive as it is if I don't use the assignement-tool in Teams. Is there a way someone in Microsoft can fix this? Please?

Best regards Oddgeir