added link for "final class constant" example.

This link will be also used from releases/8.1/en.php.

Author: mumumu

appendices/migration81/new-features.xml

@@ -153,7 +153,7 @@ $arr2 = [...$arr1, 'c' => 'd']; //[1, 'a', 'c' => 'd']
    <title>Final class constants</title>
 
    <para>
-    Added support for the <modifier>final</modifier> modifier for class constants.
+    Added support for <link linkend="language.oop5.final.example.php81">the <modifier>final</modifier> modifier for class constants</link>.
     Also, interface constants become overridable by default.
     <!-- RFC: https://wiki.php.net/rfc/final_class_const -->
    </para>

language/oop5/final.xml

@@ -60,7 +60,7 @@ class ChildClass extends BaseClass {
    </example>
   </para>
   <para>
-   <example>
+   <example xml:id="language.oop5.final.example.php81">
     <title>Final constants example as of PHP 8.1.0</title>
     <programlisting role="php">
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