made Version number selectable in About menu(commons-app#2342) (commons-app#2347)

Author: cypherop

app/src/main/res/layout/activity_about.xml

@@ -55,7 +55,8 @@
                     <TextView
                         android:id="@+id/about_version"
                         android:layout_width="wrap_content"
-                        android:layout_height="wrap_content" />
+                        android:layout_height="wrap_content"
+                        android:textIsSelectable="true" />
 
                     <fr.free.nrw.commons.ui.widget.HtmlTextView
                         android:id="@+id/about_license"