C API: Remove legacy API functions to configure Python initialization

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The following C API functions were deprecated in Python 3.11 by issue #88279:

• PySys_AddWarnOptionUnicode()
• PySys_AddWarnOption()
• PySys_AddXOption()
• PySys_HasWarnOptions()
• PySys_SetArgvEx()
• PySys_SetArgv()
• PySys_SetPath()
• Py_SetPath()
• Py_SetProgramName()
• Py_SetPythonHome()
• Py_SetStandardStreamEncoding()
• _Py_SetProgramFullPath()

IMO it's now time to remove them: the new PyConfig API is available since Python 3.8: https://docs.python.org/dev/c-api/init_config.html

Linked PRs

• gh-105145: Remove old functions to config Python init #105154
• gh-105145: Deprecate Py_GetPath() function #105179

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Oh no, too bad, I forgot to deprecate PySys_ResetWarnOptions() in Python 3.11.

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Functions like Py_GetPath() function also be deprecated.