Bump MSRV to Rust 1.80 (#13826)

crates/ruff_python_codegen/src/stylist.rs

@@ -1,9 +1,8 @@
 //! Detect code style from Python source code.
 
+use std::cell::OnceCell;
 use std::ops::Deref;
 
-use once_cell::unsync::OnceCell;
-
 use ruff_python_ast::str::Quote;
 use ruff_python_parser::{Token, TokenKind, Tokens};
 use ruff_source_file::{find_newline, LineEnding, Locator};