[issue43779] Fix possible parser/AST ref leaks

[Erlend Egeberg Aasland]

Change by Erlend Egeberg Aasland <erlend.aasland at innova.no>:


----------
title: Fix possible _PyArena_AddPyObject ref leaks -> Fix possible parser/AST ref leaks

_______________________________________
Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue43779>
_______________________________________