PR 8353 is the last piece of my long work on Py_Main() to separate code *reading* configuration and code *applying* a new configuration. My work on the new _PyPathConfig structure, and the PR should finish that work.

Extract of the commit message:

"A new _PyCoreConfig_SetPathConfig() function now recreates the path configuration from the core configuration. This function is now called very late in _Py_InitializeCore(), just before calling initimport()."