Rollup merge of #63615 - jens1o:patch-1, r=jonas-schievink
Rollup merge of #63615 - jens1o:patch-1, r=jonas-schievink

Fix typo in DoubleEndedIterator::nth_back doc

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