DUPlICATE_USING_INSTANCE documentation update

doc/classes/Node.xml

@@ -994,7 +994,7 @@
 		</constant>
 		<constant name="DUPLICATE_USE_INSTANCING" value="8" enum="DuplicateFlags">
 			Duplicate using instancing.
-			(An instance stays linked to the original so when the original changes, 			the instance changes too.)
+			An instance stays linked to the original so when the original changes, the instance changes too.
 		</constant>
 	</constants>
 </class>