Rollup merge of #49988 - clarcharr:never_docs, r=steveklabnik
Rollup merge of #49988 - clarcharr:never_docs, r=steveklabnik

Mention Result<!, E> in never docs.

Fixes #48096.

graydon/rust,GBGamer/rust,GBGamer/rust,GBGamer/rust,GBGamer/rust,aidancully/rust,aidancully/rust,graydon/rust,GBGamer/rust,GBGamer/rust,GBGamer/rust,aidancully/rust,aidancully/rust,aidancully/rust,graydon/rust,graydon/rust,aidancully/rust,graydon/rust,graydon/rust,GBGamer/rust