Fix example

Author: lpil

examples/04-working-with-other-formats/src/app/router.gleam

@@ -28,7 +28,7 @@ pub fn handle_request(req: Request) -> Response {
   // application it could be XML, protobuf, or anything else.
   let result = {
     // The GSV library is used to parse the CSV.
-    use rows <- result.try(gsv.to_lists(body))
+    use rows <- result.try(gsv.to_lists(body) |> result.replace_error(Nil))
 
     // Get the first row, which is the header row.
     use headers <- result.try(list.first(rows))

examples/04-working-with-other-formats/test/app_test.gleam

@@ -40,5 +40,5 @@ pub fn post_successful_test() {
 
   response
   |> testing.string_body
-  |> should.equal("headers,row-count\n\"name,is-cool\",2")
+  |> should.equal("headers,row-count\n\"name,is-cool\",2\n")
 }