Replace cargo-cranky with workspace lints (#4413)

Replace `cargo-cranky` (which has served us well) with workspace lints

crates/egui_demo_app/src/apps/custom3d_glow.rs

@@ -1,3 +1,5 @@
+#![allow(clippy::undocumented_unsafe_blocks)]
+
 use std::sync::Arc;
 
 use eframe::egui_glow;

crates/egui_demo_app/src/apps/http_app.rs

@@ -116,7 +116,7 @@ impl eframe::App for HttpApp {
     }
 }
 
-fn ui_url(ui: &mut egui::Ui, frame: &mut eframe::Frame, url: &mut String) -> bool {
+fn ui_url(ui: &mut egui::Ui, frame: &eframe::Frame, url: &mut String) -> bool {
     let mut trigger_fetch = false;
 
     ui.horizontal(|ui| {

crates/egui_demo_app/src/main.rs

@@ -1,6 +1,7 @@
 //! Demo app for egui
 
 #![cfg_attr(not(debug_assertions), windows_subsystem = "windows")] // hide console window on Windows in release
+#![allow(rustdoc::missing_crate_level_docs)] // it's an example
 #![allow(clippy::never_loop)] // False positive
 
 // When compiling natively: