Garbage collector article makes mixed use of `gc_ref` and `gc_refs`

[zikcheng]

In this article https://github.com/python/devguide/blob/main/internals/garbage-collector.rst, when describing how garbage collector works, it uses both gc_ref and gc_refs. And the picture uses gc_ref. And in CPython source code the variable name is gc_refs. Should we use only gc_ref and redraw the picture?

[pablogsal]

Thanks for opening this issue @zikcheng!

I think I am going to rename gc_refs to gc_ref in the text (even if the implementation uses gc_refs) as I prefer not to redraw the pictures and it really doesn't matter if it doesn't match exactly the current implementation as long as is consistent in the text.

Thanks for the catch!