Rollup merge of #126452 - compiler-errors:raw-lifetimes, r=spastorino

Implement raw lifetimes and labels (`'r#ident`)

This PR does two things:
1. Reserve lifetime prefixes, e.g. `'prefix#lt` in edition 2021.
2. Implements raw lifetimes, e.g. `'r#async` in edition 2021.

This PR additionally extends the `keyword_idents_2024` lint to also check lifetimes.

cc `@traviscross`
r? parser

Author: matthiaskrgr

crates/parser/src/lexed_str.rs

@@ -198,6 +198,13 @@ impl<'a> Converter<'a> {
                     }
                     LIFETIME_IDENT
                 }
+                rustc_lexer::TokenKind::UnknownPrefixLifetime => {
+                    err = "Unknown lifetime prefix";
+                    LIFETIME_IDENT
+                }
+                rustc_lexer::TokenKind::RawLifetime => {
+                    LIFETIME_IDENT
+                }
 
                 rustc_lexer::TokenKind::Semi => T![;],
                 rustc_lexer::TokenKind::Comma => T![,],