Fix wordings in threads.rst for correctness

[ghost]

This PR fixes a minor inconsistency in wordings used in Doc/c-api/threads.rst

as the interpreter needs to keep track of which threads may access Python objects.

[read-the-docs-community]

Documentation build overview

📚 cpython-previews | 🛠️ Build #32608467 | 📁 Comparing 1b914c7 against main (ebf6d9c)

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3 files changed

± c-api/threads.html
± whatsnew/3.16.html
± whatsnew/changelog.html

[picnixz]

Is it really correct now? there is a difference between the threads that can access objects and threads that are known to access objects. The new wording is too generic and wrong IMO. cc @ZeroIntensity

[ZeroIntensity]

Yeah, I don't think this is correct.

"threads" here refers to OS threads (in contrast to "Python" threads, which have a live thread state), so I find the phrase "[OS] threads which may access Python objects" to be confusing, because it reads as if any thread may eventually access an object at some point, which is not necessarily true. In comparison, "which [OS] threads" makes it clear that only certain threads are allowed to access objects.