change terminal ping frequency

frontend/src/views/pty/Terminal.vue

@@ -82,7 +82,7 @@ export default {
             const that = this
             this.ping = setInterval(function () {
                 that.sendMessage({Type: 3})
-            }, 10000)
+            }, 30000)
         },
         sendMessage(data) {
             this.websocket.send(JSON.stringify(data))

frontend/version.json

@@ -1 +1 @@
-{"version":"1.4.0","build_id":3,"total_build":59}
+{"version":"1.4.0","build_id":4,"total_build":60}