(Optional) Target folder for Google Drive uploads. If specified, uploaded files will be placed in this folder. Relative to the globally configured root folder. If the folder doesn’t exist, it will be created. Can be specified as a ‘/’-delimited path, or (e.g. if you have ‘/’ in a folder name) using an array of strings. NOTE: We do cache the Google-assigned ID of the folder, which means if the folder is moved (or removed) we will continue uploading to it in its new location for some time.