tkinter: add type hints to Wm methods (#4925)

tests/stubtest_whitelists/py3_common.txt

@@ -362,6 +362,7 @@ timeit.main
 tkinter.Misc.grid_propagate
 tkinter.Misc.pack_propagate
 tkinter.Tk.report_callback_exception  # A bit of a lie, since it's actually a method, but typing it as an attribute allows it to be assigned to
+tkinter.Wm.wm_iconphoto  # Default value of argument can't be used without runtime error
 tkinter.font.Font.__getitem__  # Argument name differs (doesn't matter for __dunder__ methods)
 trace.CoverageResults.__init__
 traceback.FrameSummary.__init__