Add another test case to PrecomputeStudentHashesJob spec
Add another test case to PrecomputeStudentHashesJob spec

+ This test case would have caught this issue in #1274: https://github.com/studentinsights/studentinsights/pull/1274#issuecomment-348531704

studentinsights/studentinsights,studentinsights/studentinsights,studentinsights/studentinsights,studentinsights/studentinsights