fix trailing whitespace in ChangeLog
fix trailing whitespace in ChangeLog

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