Update splash_radius assertion to use integer comparison

Changed the assertion in IconButton.before_update to compare splash_radius against 0 instead of 0.0, ensuring the value is greater than zero regardless of type.

Author: FeodorFitsner

sdk/python/packages/flet/src/flet/controls/material/icon_button.py

@@ -236,7 +236,7 @@ def toggle_icon_button(e):
 
     def before_update(self):
         super().before_update()
-        assert self.splash_radius is None or self.splash_radius > 0.0, (
+        assert self.splash_radius is None or self.splash_radius > 0, (
             f"splash_radius must be greater than 0, got {self.splash_radius}"
         )
         if (