Rollup merge of #47121 - frewsxcv:frewsxcv-vec, r=kennytm
Rollup merge of #47121 - frewsxcv:frewsxcv-vec, r=kennytm

Fix panic condition docs for Vec::insert.

Fixes https://github.com/rust-lang/rust/issues/47065.

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