Fix #1824 Make night UI properly translated

core/src/main/res/values-ar/strings.xml

@@ -259,4 +259,7 @@
   <string name="device_default">الجهاز الافتراضي</string>
   <string name="delete_history">حذف التاريخ؟</string>
   <string name="delete_bookmarks">أزل العلامات المرجعية؟</string>
+  <string name="on">تشغيل</string>
+  <string name="off">تعطيل</string>
+  <string name="auto">تلقائي</string>
 </resources>

core/src/main/res/values-qq/strings.xml

@@ -42,4 +42,7 @@
   <string name="search_history">TODO: Unclear, must be documented. See https://github.com/kiwix/overview/issues/31</string>
   <string name="save">{{Identical|Save}}</string>
   <string name="no_bookmarks">This means \"there are no bookmarks\"</string>
+  <string name="on">This is used in the settings screen to turn on the night mode.</string>
+  <string name="off">This is used in the settings screen to turn off the night mode.</string>
+  <string name="auto">This is used in the settings screen to turn the night mode on or off automatically depending upon the system settings of the phone.</string>
 </resources>

core/src/main/res/values/strings.xml

@@ -269,10 +269,13 @@
   <string name="device_default">Device Default</string>
   <string name="delete_history">Delete History?</string>
   <string name="delete_bookmarks">Delete Bookmarks?</string>
+  <string name="on">On</string>
+  <string name="off">Off</string>
+  <string name="auto">Auto</string>
   <string-array name="pref_night_modes_entries">
-    <item>On</item>
-    <item>Off</item>
-    <item>Auto</item>
+    <item>@string/on</item>
+    <item>@string/off</item>
+    <item>@string/auto</item>
   </string-array>
   <string-array name="pref_night_modes_values">
     <item>2</item>