test_wm_iconbitmap() timeout after 10 min on "macOS / build and test (macos-26-intel)" CI

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Example of failure: https://github.com/python/cpython/actions/runs/23552862012/job/68571481619?pr=146357

(...)
test_wm_attribute (test.test_tkinter.test_misc.WmTest.test_wm_attribute) ... ok
test_wm_iconbitmap (test.test_tkinter.test_misc.WmTest.test_wm_iconbitmap) ... Timeout (0:10:00)!
Thread 0x00007ff85c48cc00 (most recent call first):
  File "/Users/runner/work/cpython/cpython/Lib/tkinter/__init__.py", line 2345 in wm_iconbitmap
  File "/Users/runner/work/cpython/cpython/Lib/test/test_tkinter/test_misc.py", line 582 in test_wm_iconbitmap
  File "/Users/runner/work/cpython/cpython/Lib/unittest/case.py", line 613 in _callTestMethod
  File "/Users/runner/work/cpython/cpython/Lib/unittest/case.py", line 667 in run
(...)

test.pythoninfo:

tkinter.TCL_VERSION: 9.0
tkinter.TK_VERSION: 9.0
tkinter.info_patchlevel: 9.0.3

The test_wm_iconbitmap() test was added by commit 58e9f95.

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"Lib/tkinter/__init__.py, line 2345 in wm_iconbitmap" is the last line of wm_iconbitmap(), where I added the comment:

    def wm_iconbitmap(self, bitmap=None, default=None):
        """Set bitmap for the iconified widget to BITMAP. Return
        the bitmap if None is given.

        Under Windows, the DEFAULT parameter can be used to set the icon
        for the widget and any descendants that don't have an icon set
        explicitly.  DEFAULT can be the relative path to a .ico file
        (example: root.iconbitmap(default='myicon.ico') ).  See Tk
        documentation for more information."""
        if default is not None:
            return self.tk.call('wm', 'iconbitmap', self._w, '-default', default)
        else:
            return self.tk.call('wm', 'iconbitmap', self._w, bitmap) # <=== HANGS HERE