fix: Update line count in To-Do app tutorial (#6375)

A very, very small detail... :

Not 163 but now 164 lines for todo script in the real code listing:
https://github.com/flet-dev/flet/blob/main/sdk/python/examples/apps/todo/basic/main.py

Co-authored-by: Feodor Fitsner <feodor@appveyor.com>

Author: GrCOTE7

website/docs/tutorials/todo.md

@@ -8,7 +8,7 @@ import {CodeExample, Image} from '@site/src/components/crocodocs';
 In this tutorial we will show you, step-by-step, how to create a To-Do app in Python
 using Flet framework and then publish it as a desktop, mobile or web app.
 The app is a single-file console program of just
-[167 lines (formatted!) of Python code](https://github.com/flet-dev/flet/blob/main/sdk/python/examples/apps/todo/basic/main.py),
+[164 lines (formatted!) of Python code](https://github.com/flet-dev/flet/blob/main/sdk/python/examples/apps/todo/basic/main.py),
 yet it is a multi-platform application with rich, responsive UI:
 
 <Image src="examples/tutorials/todo/media/complete-demo-web.gif" width="55%" />