Greatly simplify lifetime captures in edition 2024

compiler/rustc_mir_transform/src/coverage/spans.rs

@@ -1,6 +1,5 @@
 use std::collections::VecDeque;
 
-use rustc_data_structures::captures::Captures;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_middle::mir;
 use rustc_span::{DesugaringKind, ExpnKind, MacroKind, Span};
@@ -182,7 +181,7 @@ fn divide_spans_into_buckets(input_covspans: Vec<Covspan>, holes: &[Hole]) -> Ve
 fn drain_front_while<'a, T>(
     queue: &'a mut VecDeque<T>,
     mut pred_fn: impl FnMut(&T) -> bool,
-) -> impl Iterator<Item = T> + Captures<'a> {
+) -> impl Iterator<Item = T> {
     std::iter::from_fn(move || if pred_fn(queue.front()?) { queue.pop_front() } else { None })
 }