use 'sed -i$BACKUP_SUFFIX' instead of 'sed -i $BACKUP_SUFFIX', so that it works with both BSD and GNU versions of sed
use 'sed -i$BACKUP_SUFFIX' instead of 'sed -i $BACKUP_SUFFIX', so that it works with both BSD and GNU versions of sed

phetsims/chipper,concord-consortium/chipper,phetsims/chipper,concord-consortium/chipper,phetsims/chipper,concord-consortium/chipper,concord-consortium/chipper