Increase MSRV to 1.67 (#3234)

* Bump MSRV to 1.67

* clippy fixes

* cargo clippy: inline format args

* Add `clippy::uninlined_format_args` to cranky lints

* Fix clippy on wasm

* More clippy fixes

crates/egui_demo_app/src/apps/http_app.rs

@@ -133,7 +133,7 @@ fn ui_url(ui: &mut egui::Ui, frame: &mut eframe::Frame, url: &mut String) -> boo
         if ui.button("Random image").clicked() {
             let seed = ui.input(|i| i.time);
             let side = 640;
-            *url = format!("https://picsum.photos/seed/{}/{}", seed, side);
+            *url = format!("https://picsum.photos/seed/{seed}/{side}");
             trigger_fetch = true;
         }
     });

crates/egui_demo_app/src/backend_panel.rs

@@ -232,8 +232,7 @@ impl BackendPanel {
                 if ui
                     .add_enabled(enabled, egui::Button::new("Reset"))
                     .on_hover_text(format!(
-                        "Reset scale to native value ({:.1})",
-                        native_pixels_per_point
+                        "Reset scale to native value ({native_pixels_per_point:.1})"
                     ))
                     .clicked()
                 {
@@ -441,7 +440,7 @@ impl EguiWindows {
                     .stick_to_bottom(true)
                     .show(ui, |ui| {
                         for event in output_event_history {
-                            ui.label(format!("{:?}", event));
+                            ui.label(format!("{event:?}"));
                         }
                     });
             });

crates/egui_demo_app/src/wrap_app.rs

@@ -354,7 +354,7 @@ impl WrapApp {
             {
                 selected_anchor = anchor;
                 if frame.is_web() {
-                    ui.output_mut(|o| o.open_url(format!("#{}", anchor)));
+                    ui.output_mut(|o| o.open_url(format!("#{anchor}")));
                 }
             }
         }