Pattern Migration 2024: try to suggest eliding redundant binding modifiers
This is based on #136475. Only the last commit is new.
This is a simpler, more restrictive alternative to #136496, meant to partially address #136047. If a pattern can be migrated to Rust 2024 solely by removing redundant binding modifiers, this will make that suggestion; otherwise, it uses the old suggestion of making the pattern fully explicit.
Relevant tracking issue: #131414
``@rustbot`` label A-diagnostics A-patterns A-edition-2024
r? ``@Nadrieril``
20f9e973d9