[issue32374] Document that m_traverse for multi-phase initialized modules can be called with m_state=NULL

[miss-islington]

Change by miss-islington <mariatta.wijaya+miss-islington at gmail.com>:


----------
pull_requests: +6784

_______________________________________
Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue32374>
_______________________________________