Adds a file to an item in cloud storage
Value
Success message invisibly. NOTE: cloud processing can take some time so the added file may not appear immediately. For this reason, a sciencebase item json is NOT returned as is done with other similar functions.
Examples
if (FALSE) {
res <- item_create(user_id(), "testing 123")
cat("foo bar", file = "foobar.txt")
item_upload_cloud(res$id, "foobar.txt")
}