Use us-east-1 when running external grading with batch
Use us-east-1 when running external grading with batch

tbretl/PrairieLearn,rbessick5/PrairieLearn,tbretl/PrairieLearn,parasgithub/PrairieLearn,tbretl/PrairieLearn,tbretl/PrairieLearn,rbessick5/PrairieLearn,mwest1066/PrairieLearn,rbessick5/PrairieLearn,parasgithub/PrairieLearn,parasgithub/PrairieLearn,jakebailey/PrairieLearn,jakebailey/PrairieLearn,parasgithub/PrairieLearn,jakebailey/PrairieLearn,rbessick5/PrairieLearn,parasgithub/PrairieLearn,mwest1066/PrairieLearn,tbretl/PrairieLearn,mwest1066/PrairieLearn,mwest1066/PrairieLearn,rbessick5/PrairieLearn,jakebailey/PrairieLearn,mwest1066/PrairieLearn