fix: fix the app icon on the device

android/AndroidManifest.xml

 <?xml version="1.0"?>
 <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="io.qt.qtdesignviewer"
-    android:installLocation="auto" android:versionCode="12" android:versionName="1.2">
+    android:installLocation="auto" android:versionCode="13" android:versionName="1.2">
     <!-- %%INSERT_PERMISSIONS -->
     <!-- %%INSERT_FEATURES -->
-    <supports-screens android:anyDensity="true" android:largeScreens="true" android:normalScreens="true" android:smallScreens="true"/>
-    <application android:name="org.qtproject.qt.android.bindings.QtApplication" android:extractNativeLibs="true" android:hardwareAccelerated="true" android:label="Qt Design Viewer" android:requestLegacyExternalStorage="true" android:allowNativeHeapPointerTagging="false">
+    <supports-screens android:anyDensity="true" android:largeScreens="true"
+        android:normalScreens="true" android:smallScreens="true" />
+    <application android:name="org.qtproject.qt.android.bindings.QtApplication"
+        android:extractNativeLibs="true" android:hardwareAccelerated="true"
+        android:label="Qt Design Viewer" android:requestLegacyExternalStorage="true"
+        android:allowNativeHeapPointerTagging="false" android:icon="@mipmap/app_icon">
         <activity android:name="org.qtproject.qt.android.bindings.QtActivity" android:configChanges="orientation|uiMode|screenLayout|screenSize|smallestScreenSize|layoutDirection|locale|fontScale|keyboard|keyboardHidden|navigation|mcc|mnc|density" android:label="Qt Design Viewer" android:launchMode="singleTop" android:screenOrientation="unspecified" android:exported="true">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN"/>

src/main.cpp

@@ -25,9 +25,7 @@
 
 #include <android/log.h>
 #include <QApplication>
-#include <QDebug>
 #include <QQmlContext>
-#include <QSurfaceFormat>
 
 #include "backend.h"