gh-140729: Fix the cProfile module when the executed script contains calls to multiprocessing.Process

[YvesDup]

When profilng the ttt.py script via cProfile module ,

import multiprocessing

def worker_proc(x):
    return x ** 99

def main_proc():
    p = multiprocessing.Process(target=worker_proc, args=(10,))
    p.start()
    p.join()

if __name__ == "__main__":
    main_proc()

./python.exe -m cProfile ttt.py 

an error occurs:

AttributeError: module '__main__' has no attribute 'worker_proc'

This fix does not apply to the profile module, which is deprecated and will be removed in python 3.17.

• Issue: 3.15 profiling, can't use ProcessPoolExecutor.map() in a simple script #140729

[aisk]

I suggest using textwrap.dedent to preserve the indentation, even though the other tests in this file don't do so:

        test_script = textwrap.dedent(f'''
        import multiprocess
        ....
        ''')

[aisk]

Suggested change

	Fix pickling error in the cProfile module when using ``multiprocessing.Process``
	Fix pickling error in the :mode:`cProfile` module when using :class:`multiprocessing.Process`