Rollup merge of #40052 - GuillaumeGomez:sunc_docs, r=frewsxcv
Rollup merge of #40052 - GuillaumeGomez:sunc_docs, r=frewsxcv

Add missing urls in MutexGuard docs

r? @frewsxcv

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