[Doc-SIG] Faster jump table for the builtin functions

[Julien Palard]

I don't know for you, but I often use by browser search to find a 
builtin function because it's faster than my eyes on the jump table :(

I think little enhancements come from little frustrations...

So I think it can be enhanced and I opened 
https://github.com/python/cpython/pull/21376 to try myself at it, but 
I'm bad at UI/UX so I'd happily get feedback on it.

Bests,
-- 
[Julien Palard](https://mdk.fr)