Enable more clippy lints (#6853)

* Follows https://github.com/emilk/egui/pull/6848

examples/custom_style/src/main.rs

@@ -4,7 +4,7 @@
 use eframe::egui::{
     self, global_theme_preference_buttons, style::Selection, Color32, Stroke, Style, Theme,
 };
-use egui_demo_lib::{View, WidgetGallery};
+use egui_demo_lib::{View as _, WidgetGallery};
 
 fn main() -> eframe::Result {
     env_logger::init(); // Log to stderr (if you run with `RUST_LOG=debug`).

examples/puffin_profiler/src/main.rs

@@ -165,7 +165,7 @@ fn start_puffin_server() {
 
             // We can store the server if we want, but in this case we just want
             // it to keep running. Dropping it closes the server, so let's not drop it!
-            #[allow(clippy::mem_forget)]
+            #[expect(clippy::mem_forget)]
             std::mem::forget(puffin_server);
         }
         Err(err) => {