update safety example

_includes/body.html

@@ -72,7 +72,7 @@
 						In a setting of <strong>critical system of aircraft collision avoidance</strong>, we aim to prove that for certain configurations of the two planes the neural network will answer as expected.<br>
 						For example, we could aim to prove:<br>
 						<div class="has-text-centered">
-						<img src="{{ '/assets/images/safety-example.png' | relative_url }}">
+						<img src="{{ '/assets/images/safety-prop.png' | relative_url }}">
 						</div>
 						</p>
 					</div>