Fix missing get_rl_tempfile in __all__ export - #16311

According to mypy_primer, this change has no effect on the checked open source code. 🤖🎉

this is causing CI to fail -- does it actually exist in __all__ in the runtime package?

This is indeed a problem, but it is present in the library itself, both in 4.3.1 version (the last version supported by typeshed) and in the source code of the latest version. As I understand it, in situations like this, the usual approach is to follow the actual runtime behavior and keep the stubs consistent with it.

I suggest reporting the issue to the reportlab development team:

Please do not use this for issue reporting etc; use the mail list at
https://pairlist2.pair.net/mailman/listinfo/reportlab-users

But this address didn't open for me, so I found this mirror on Google Groups: https://groups.google.com/g/reportlab-users

Nice find. Reported in the mailing list.