[libc] [llvm] [libc][docs] add redirect for math/index.html (PR #120274)

[Aiden Grossman via llvm-commits]

boomanaiden154 wrote:

Surprised I have not run into that policy yet...

Can you do a venv?

```
python3 -m venv env
source ./env/bin/activate
pip3 install pip-tools
```

https://github.com/llvm/llvm-project/pull/120274