Update PyCode_GetName/FileName usage in torch patch

Author: msimacek

graalpython/lib-graalpython/patches/torch/torch-1.13.1.patch

@@ -310,20 +310,27 @@ index 8c9ed1d7..5183a325 100644
    }
  }
 diff --git a/torch/csrc/jit/python/python_tracer.cpp b/torch/csrc/jit/python/python_tracer.cpp
-index 78676e2e..ecc76ea9 100644
+index 78676e2e..e6a3caf0 100644
 --- a/torch/csrc/jit/python/python_tracer.cpp
 +++ b/torch/csrc/jit/python/python_tracer.cpp
-@@ -33,8 +33,8 @@ std::vector<StackEntry> _pythonCallstack() {
+@@ -33,11 +33,15 @@ std::vector<StackEntry> _pythonCallstack() {
    while (nullptr != frame) {
      auto code = THPCodeObjectPtr(PyFrame_GetCode(frame));
      size_t line = PyCode_Addr2Line(code.get(), PyFrame_GetLasti(frame));
 -    std::string filename = THPUtils_unpackString(code->co_filename);
 -    std::string funcname = THPUtils_unpackString(code->co_name);
-+    std::string filename = THPUtils_unpackString(PyCode_GetFileName(code));
-+    std::string funcname = THPUtils_unpackString(PyCode_GetName(code));
++    PyObject* filenameObj = PyCode_GetFileName(code);
++    std::string filename = THPUtils_unpackString(filenameObj);
++    PyObject* funcnameObj = PyCode_GetName(code);
++    std::string funcname = THPUtils_unpackString(funcnameObj);
      auto source = std::make_shared<Source>(funcname, filename, line);
      entries.emplace_back(
          StackEntry{funcname, SourceRange(source, 0, funcname.size())});
++    Py_DECREF(funcnameObj);
++    Py_DECREF(filenameObj);
+     auto new_frame = PyFrame_GetBack(frame);
+     Py_DECREF(frame);
+     frame = new_frame;
 diff --git a/torch/csrc/utils/python_compat.h b/torch/csrc/utils/python_compat.h
 index 44911527..d3ad9c54 100644
 --- a/torch/csrc/utils/python_compat.h