[skip-revcheck] Fix typo

Author: kamil-tekiela

features/gc.xml

@@ -253,7 +253,7 @@ a: (refcount=1, is_ref=0)=array (
     </para>
     <para>
      <example>
-      <title>Adding the array itself as an element of it self</title>
+      <title>Adding the array as an element of itself</title>
       <programlisting role="php">
 <![CDATA[
 <?php