Update app.js

@@ -104,7 +104,7 @@ async function handleEvent(event) {
       body: fs.readFileSync("./photo/1.png")
       body: fs.readFileSync("./photo/1.png")
       };
       };
       app.get('/photo',(req,res)=>{
       app.get('/photo',(req,res)=>{
-        res.send(chunk);
+        res.send(chunk+"png");
       })
       })
       /*
       /*
       request.post(options, function (error, response, body) {
       request.post(options, function (error, response, body) {