Update index.md: changed Dragana's date

Author: luigiapetre

content/post/tutorials/index.md

@@ -60,7 +60,7 @@ Here are the details of the scheduled Zoom meeting:
 
 ## 2025
 <!------------------------------------------------------------------------------------>
-- <img src="photos/DraganaMilovancevic.jpg" style="width:200px;" /> June 27, 2025, 2 pm CEST: [Dragana Milovancevic](https://people.epfl.ch/dragana.milovancevic/?lang=en), [EPFL](https://lara.epfl.ch/w/), Switzerland: **Formal Autograding in a Classroom**
+- <img src="photos/DraganaMilovancevic.jpg" style="width:200px;" /> August 1, 2025, 3 pm CEST: [Dragana Milovancevic](https://people.epfl.ch/dragana.milovancevic/?lang=en), [EPFL](https://lara.epfl.ch/w/), Switzerland: **Formal Autograding in a Classroom**
 
 - {{< spoiler text="Abstract of the tutorial" >}}