Rollup merge of #140791 - xizheyin:issue-140761, r=ibraheemdev

std: explain prefer `TryInto` over `TryFrom` when specifying traits bounds on generic function

Fixes #140761

This PR keeps the explanations of `Into` and `From` consistent and adds explanations for `TryInto` and `TryFrom`.

r? libs

Author: matthiaskrgr