add "deleted_at IS NULL" when finding assessment questions by qid; close #508
add "deleted_at IS NULL" when finding assessment questions by qid; close #508

rbessick5/PrairieLearn,rbessick5/PrairieLearn,tbretl/PrairieLearn,kevinwang/PrairieLearn,jakebailey/PrairieLearn,parasgithub/PrairieLearn,mwest1066/PrairieLearn,rbessick5/PrairieLearn,tbretl/PrairieLearn,mwest1066/PrairieLearn,lotrfan/PrairieLearn,mwest1066/PrairieLearn,parasgithub/PrairieLearn,lotrfan/PrairieLearn,lotrfan/PrairieLearn,kevinwang/PrairieLearn,PrairieLearn/PrairieLearnHack,lotrfan/PrairieLearn,kevinwang/PrairieLearn,lotrfan/PrairieLearn,PrairieLearn/PrairieLearnHack,jakebailey/PrairieLearn,PrairieLearn/PrairieLearnHack,PrairieLearn/PrairieLearnHack,mwest1066/PrairieLearn,PrairieLearn/PrairieLearnHack,lotrfan/PrairieLearn,PrairieLearn/PrairieLearnHack,rbessick5/PrairieLearn,tbretl/PrairieLearn,kevinwang/PrairieLearn,lotrfan/PrairieLearn,parasgithub/PrairieLearn,parasgithub/PrairieLearn,PrairieLearn/PrairieLearnHack,tbretl/PrairieLearn,mwest1066/PrairieLearn,kevinwang/PrairieLearn,jakebailey/PrairieLearn,jakebailey/PrairieLearn,tbretl/PrairieLearn,parasgithub/PrairieLearn,PrairieLearn/PrairieLearnHack,rbessick5/PrairieLearn,kevinwang/PrairieLearn,kevinwang/PrairieLearn