added 1 missing type hint

Author: alexn11

fractals/julia_sets.py

@@ -74,7 +74,7 @@ def iterate_function(
     function_params: Any,
     nb_iterations: int,
     z_0: numpy.ndarray,
-    infinity=None,
+    infinity: float = None,
 ) -> numpy.ndarray:
     """
     Iterate the function "eval_function" exactly nb_iterations times.