Revert "dates: refresh diagnostics/ and tests/ annotated dates to August 2025"#2567

tshepang merged 1 commit intomasterrust-lang/rustc-dev-guide:masterfrom

revert-2556-date-sweep-2025-08-diag-testsrust-lang/rustc-dev-guide:revert-2556-date-sweep-2025-08-diag-testsCopy head branch name to clipboard