the android toast use single instance

android/src/main/kotlin/io/github/ponnamkarthik/toast/fluttertoast/FluttertoastPlugin.kt

@@ -46,7 +46,7 @@ class FluttertoastPlugin(context: Context): MethodCallHandler {
 
         val toast: Toast = this.toast?:Toast.makeText(ctx, msg, Toast.LENGTH_SHORT);
         this.toast = toast
-        toast.text = msg;
+        toast.setText(msg)
       if(length.equals("long")) {
           toast.duration = Toast.LENGTH_LONG
       } else {