Fix issue where we offered to use a collection expression when teh user didn't have a viable Add method#79157

CyrusNajmabadi merged 2 commits intodotnet:maindotnet/roslyn:mainfrom

CyrusNajmabadi:useCollectionExprInvalidAddCyrusNajmabadi/roslyn:useCollectionExprInvalidAddCopy head branch name to clipboard