Auto merge of #34313 - frewsxcv:panicking-example, r=steveklabnik
Auto merge of #34313 - frewsxcv:panicking-example, r=steveklabnik

Add example in docs for `std::thread::panicking`.

None

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