update list.md
update list.md

remove duplicate additional resources section
ksigler7/docs,Whatthefoxsays/docs,sendgrid/docs,katieporter/docs,Whatthefoxsays/docs,katieporter/docs,katieporter/docs,Whatthefoxsays/docs,sendgrid/docs,ksigler7/docs,katieporter/docs,katieporter/docs,ksigler7/docs,sendgrid/docs