book: Fix clippy warnings

Author: Hofer-Julian

book/listings/actions/3/main.rs

@@ -22,7 +22,7 @@ fn main() {
 fn build_ui(app: &Application) {
     let original_state = 0;
     let label = Label::builder()
-        .label(&format!("Counter: {original_state}"))
+        .label(format!("Counter: {original_state}"))
         .build();
 
     // Create a button with label

book/listings/actions/4/main.rs

@@ -22,7 +22,7 @@ fn main() {
 fn build_ui(app: &Application) {
     let original_state = 0;
     let label = Label::builder()
-        .label(&format!("Counter: {original_state}"))
+        .label(format!("Counter: {original_state}"))
         .build();
     // ANCHOR: button_builder
     // Create a button with label and action

book/listings/actions/5/window/imp.rs

@@ -1,5 +1,4 @@
 use glib::subclass::InitializingObject;
-use gtk::prelude::*;
 use gtk::subclass::prelude::*;
 use gtk::{glib, CompositeTemplate, Label};
 

book/listings/actions/6/window/imp.rs

@@ -1,5 +1,4 @@
 use glib::subclass::InitializingObject;
-use gtk::prelude::*;
 use gtk::subclass::prelude::*;
 use gtk::{glib, Button, CompositeTemplate, Label};
 

book/listings/actions/7/window/imp.rs

@@ -1,6 +1,5 @@
 use gio::Settings;
 use glib::subclass::InitializingObject;
-use gtk::prelude::*;
 use gtk::subclass::prelude::*;
 use gtk::{gio, glib, Button, CompositeTemplate, Label};
 use once_cell::sync::OnceCell;

book/listings/css/6/window/imp.rs

@@ -1,5 +1,4 @@
 use glib::subclass::InitializingObject;
-use gtk::prelude::*;
 use gtk::subclass::prelude::*;
 use gtk::{glib, CompositeTemplate};
 

book/listings/css/7/window/imp.rs

@@ -1,5 +1,4 @@
 use glib::subclass::InitializingObject;
-use gtk::prelude::*;
 use gtk::subclass::prelude::*;
 use gtk::{glib, CompositeTemplate};
 

book/listings/css/8/window/imp.rs

@@ -1,5 +1,4 @@
 use glib::subclass::InitializingObject;
-use gtk::prelude::*;
 use gtk::subclass::prelude::*;
 use gtk::{glib, CompositeTemplate};
 

book/listings/css/9/window/imp.rs

@@ -1,5 +1,4 @@
 use glib::subclass::InitializingObject;
-use gtk::prelude::*;
 use gtk::subclass::prelude::*;
 use gtk::{glib, CompositeTemplate};
 

book/listings/todo/1/task_row/imp.rs

@@ -1,7 +1,6 @@
 use std::cell::RefCell;
 
 use glib::Binding;
-use gtk::prelude::*;
 use gtk::subclass::prelude::*;
 use gtk::{glib, CheckButton, CompositeTemplate, Label};