Fix dangerous reference count decrement

Author: smurav

Python/instrumentation.c

@@ -2559,19 +2559,19 @@ PyObject *_Py_CreateMonitoringObject(void)
     if (err) goto error;
     PyObject *val = PyLong_FromLong(PY_MONITORING_DEBUGGER_ID);
     err = PyObject_SetAttrString(mod, "DEBUGGER_ID", val);
-    Py_DECREF(val);
+    Py_XDECREF(val);
     if (err) goto error;
     val = PyLong_FromLong(PY_MONITORING_COVERAGE_ID);
     err = PyObject_SetAttrString(mod, "COVERAGE_ID", val);
-    Py_DECREF(val);
+    Py_XDECREF(val);
     if (err) goto error;
     val = PyLong_FromLong(PY_MONITORING_PROFILER_ID);
     err = PyObject_SetAttrString(mod, "PROFILER_ID", val);
-    Py_DECREF(val);
+    Py_XDECREF(val);
     if (err) goto error;
     val = PyLong_FromLong(PY_MONITORING_OPTIMIZER_ID);
     err = PyObject_SetAttrString(mod, "OPTIMIZER_ID", val);
-    Py_DECREF(val);
+    Py_XDECREF(val);
     if (err) goto error;
     return mod;
 error: