[py] Make sure py.typed file is included in the library

Author: AutomatedTester

py/BUILD.bazel

@@ -72,6 +72,7 @@ py_library(
         exclude = ["generate.py"],
     ),
     data = [
+        "selenium/py.typed",
         ":find-elements",
         ":firefox-driver-prefs",
         ":get-attribute",