tdf#138987 pyuno: PyEval_InitThreads is a no-op in Python 3.9

Change-Id: I7cf95ab1f237e315e8bd80b47758839bca34f970
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/107946
Reviewed-by: Michael Stahl <michael.stahl@cib.de>
Tested-by: Jenkins
diff --git a/pyuno/source/module/pyuno_module.cxx b/pyuno/source/module/pyuno_module.cxx
index 4a9d192..35986b364 100644
--- a/pyuno/source/module/pyuno_module.cxx
+++ b/pyuno/source/module/pyuno_module.cxx
@@ -883,7 +883,9 @@ PyObject* PyInit_pyuno()
    PyUNO_initType();
    PyUNOStruct_initType();
    // noop when called already, otherwise needed to allow multiple threads
#if PY_VERSION_HEX < 0x03090000
    PyEval_InitThreads();
#endif
    static struct PyModuleDef moduledef =
    {
        PyModuleDef_HEAD_INIT,