bpo-44113: Deprecate old functions to config Python init (GH-26060)

Deprecate the following functions to configure the Python
initialization:

* PySys_AddWarnOption()
* PySys_AddWarnOptionUnicode()
* PySys_AddXOption()
* PySys_HasWarnOptions()
* Py_SetPath()
* Py_SetProgramName()
* Py_SetPythonHome()
* Py_SetStandardStreamEncoding()
* _Py_SetProgramFullPath()

Use the new PyConfig API of the Python Initialization Configuration
instead (PEP 587).