Rollup merge of #48474 - christianpoveda:new_cell_docs, r=steveklabnik
Rollup merge of #48474 - christianpoveda:new_cell_docs, r=steveklabnik

New Cell docs

This fixes https://github.com/rust-lang/rust/issues/44061

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