Behat webserver logs: grade leads to "already has a grade" on restore of removed quiz

Originally from MDL-68459 (now split from it), we need to check (and fix if needed) why this is being reported in logs:

Problem D: User id 'xxxxxx' already has a grade (recycle bin, maybe it's ok). It happens 1 times.

Happens with scenario "Delete and restore a quiz with user data.

95836:[Sat Apr 18 08:37:30.503142 2020] [php7:notice] [pid 24203] [client 172.29.0.9:52928] User id '111001' already has a grade entry for grade item id '253000', referer: http://runcd9a035d2c706523/behatrun2/admin/tool/recyclebin/index.php?contextid=101002

The scenario does delete a quiz and then restores it back from the bin. Worth looking which grade-item is still there, because it shouldn't be the quiz one.

If it's correct and it's just a message informing that existing course... grade won't be restored... all ok.

But it the grade is the quiz one... then we need to investigate why it was not removed when the activity was deleted, because there may be an underlying bug.