Auto merge of #54798 - matthewjasper:free-region-closure-errors, r=nikomatsakis

[NLL]  Improve closure region bound errors

Previously, we would report free region errors that originate from closure with the span of the closure and a "closure body requires ..." message. This is now updated to use a reason and span from inside the closure.

diff --cc src/librustc/ich/impls_mir.rs
Simple merge

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