[3.13] Doc: C API: Fix Py_NewInterpreterFromConfig example code (GH-126667) (#127201)

Doc: C API: Fix `Py_NewInterpreterFromConfig` example code (GH-126667)
(cherry picked from commit e3038e9)

Co-authored-by: Richard Hansen <[email protected]>

Author: miss-islington

Doc/c-api/init.rst

@@ -1688,7 +1688,11 @@ function. You can create and destroy them using the following functions:
           .check_multi_interp_extensions = 1,
           .gil = PyInterpreterConfig_OWN_GIL,
       };
-      PyThreadState *tstate = Py_NewInterpreterFromConfig(&config);
+      PyThreadState *tstate = NULL;
+      PyStatus status = Py_NewInterpreterFromConfig(&tstate, &config);
+      if (PyStatus_Exception(status)) {
+          Py_ExitStatusException(status);
+      }
 
    Note that the config is used only briefly and does not get modified.
    During initialization the config's values are converted into various