Add changes to changelog.
Add changes to changelog.

davidszotten/pytest,eli-b/pytest,ddboline/pytest,tomviner/pytest,MichaelAquilina/pytest,alfredodeza/pytest,hpk42/pytest,rmfitzpatrick/pytest,malinoff/pytest,nicoddemus/pytest,etataurov/pytest,txomon/pytest,RonnyPfannschmidt/pytest,pytest-dev/pytest,The-Compiler/pytest,markshao/pytest,nicoddemus/pytest,The-Compiler/pytest,tgoodlet/pytest,vmalloc/dessert,pfctdayelise/pytest,hackebrot/pytest,tomviner/pytest,tareqalayan/pytest,Akasurde/pytest,hpk42/pytest,skylarjhdownes/pytest,flub/pytest,jaraco/pytest