docs: fix simple typo, resoultion -> resolution

There is a small typo in chapter08/maze.py.

Should read `resolution` rather than `resoultion`.

chapter08/maze.py

@@ -89,7 +89,7 @@ def __init__(self):
         self.resolution = 1
 
     # extend a state to a higher resolution maze
-    # @state: state in lower resoultion maze
+    # @state: state in lower resolution maze
     # @factor: extension factor, one state will become factor^2 states after extension
     def extend_state(self, state, factor):
         new_state = [state[0] * factor, state[1] * factor]