Auto merge of #51248 - fabric-and-ink:newtype_index_debrujin, r=nikomatsakis

Declare DebruijnIndex via newtype_index macro

Part of #49887

Declare `DebruijnIndex` via the `newtype_index` macro.

diff --cc src/librustc/middle/resolve_lifetime.rs
Simple merge

diff --cc src/librustc/ty/mod.rs
Simple merge

diff --cc src/librustc/ty/sty.rs
Simple merge

diff --cc src/librustc/ty/util.rs
Simple merge

diff --cc src/librustc/util/ppaux.rs
Simple merge

diff --cc src/librustc_driver/test.rs
Simple merge

diff --cc src/librustc_typeck/collect.rs
Simple merge

diff --cc src/test/ui/nll/closure-requirements/propagate-approximated-shorter-to-static-no-bound.stderr
Simple merge

diff --cc src/test/ui/nll/closure-requirements/propagate-approximated-shorter-to-static-wrong-bound.stderr
Simple merge