Renamed Set wallpaper to Set as wallpaper commons-app#1813 (commons-app#1818)

Author: VaishSiddharth

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

@@ -305,7 +305,7 @@
 
   <string name="successful_wikidata_edit">Image successfully added to %1$s on Wikidata!</string>
   <string name="wikidata_edit_failure">Failed to update corresponding Wikidata entity!</string>
-  <string name="menu_set_wallpaper">Set wallpaper</string>
+  <string name="menu_set_wallpaper">Set as wallpaper</string>
   <string name="wallpaper_set_successfully">Wallpaper set successfully!</string>
   <string name="quiz">Quiz</string>
   <string name="quiz_question_string">Is this picture OK to upload?</string>