[py] Correct Type Hinting on option method. Fixes #9210

Dicts are allowed to be passed in as well as the current values already
on the method.

py/selenium/webdriver/chromium/options.py

@@ -121,7 +121,7 @@ def experimental_options(self) -> dict:
         """
         return self._experimental_options
 
-    def add_experimental_option(self, name: str, value: Union[str, int]):
+    def add_experimental_option(self, name: str, value: Union[str, int, dict]):
         """
         Adds an experimental option which is passed to chromium.