Auto merge of #90463 - matthiaskrgr:rollup-eljk9vo, r=matthiaskrgr

Rollup of 8 pull requests

Successful merges:

 - #89826 (Feature gate + make must_not_suspend allow-by-default)
 - #89929 (Handling submodule update failures more gracefully from x.py)
 - #90333 (rustdoc: remove flicker during page load)
 - #90349 (Fix rare ICE during typeck in rustdoc scrape_examples)
 - #90398 (Document `doc(keyword)` unstable attribute)
 - #90441 (Test that promotion follows references when looking for drop)
 - #90450 (Remove `rustc_hir::hir_id::HirIdVec`)
 - #90452 (Remove unnecessary `Option` from `promote_candidate` return type)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

compiler/rustc_lint/src/lib.rs

@@ -303,7 +303,6 @@ fn register_builtins(store: &mut LintStore, no_interleave_lints: bool) {
         UNUSED_LABELS,
         UNUSED_PARENS,
         UNUSED_BRACES,
-        MUST_NOT_SUSPEND,
         REDUNDANT_SEMICOLONS
     );