docs(form): add dollar sign back to setSubmitted()
docs(form): add dollar sign back to setSubmitted()

Dollar sign was missing for setSubmitted() due to 7b40f8f43aa1046907b9359bf9dab2ee688007fc, just
adding it back in ヽ(^。^)ノ

Closes #8772

ggershoni/angular.js,ggershoni/angular.js,ggershoni/angular.js,ggershoni/angular.js