PyEval_InitThreads() is deprecated

`Py_Initialize()` does it since 3.7, it's a noop and deprecated since 3.9.

https://docs.python.org/3/c-api/init.html#c.PyEval_InitThreads

Signed-off-by: Steffen Jaeckel <s@jaeckel.eu>

src/plugins/python_api.c

@@ -1609,7 +1609,9 @@ python_init_prof(void)
 #ifdef PY_IS_PYTHON3
     PyImport_AppendInittab("prof", python_api_init);
     Py_Initialize();
+#if PY_VERSION_HEX < 0x03070000
     PyEval_InitThreads();
+#endif
 #else
     Py_Initialize();
     PyEval_InitThreads();