replace screenshot

README.md

@@ -9,7 +9,7 @@
             "type": "topjs",
             "request": "launch",
             "name": "Launch Debugger",
-            "port": "30992",
+            "port": 30992,
             "runtimeExecutable": "topjs3",
             "program": "${workspaceFolder}/${command:getProgramPath}"
         }
@@ -28,4 +28,4 @@
 
 截图
 
-![screenshot](./assets/screenshot.jpg)
\ No newline at end of file
+![screenshot](./assets/screenshot.gif)
\ No newline at end of file