pcntl_waitid(): add changelog section (#4949)

Page: https://www.php.net/manual/en/function.pcntl-waitid.php

The PHP 8.5 new `$resource_usage` parameter was added to the docs in PR 3854, but no changelog section was added, giving the reader the impression that the parameter was part of the function signature since the function was introduced, which is not true.

Refs:
* php/php-src 15921

Co-authored-by: jrfnl <[email protected]>

Author: jrfnl

reference/pcntl/functions/pcntl-waitid.xml

@@ -320,6 +320,28 @@
   </table>
  </refsect1>
 
+ <refsect1 role="changelog">
+  &reftitle.changelog;
+  <informaltable>
+   <tgroup cols="2">
+    <thead>
+     <row>
+      <entry>&Version;</entry>
+      <entry>&Description;</entry>
+     </row>
+    </thead>
+    <tbody>
+     <row>
+      <entry>8.5.0</entry>
+      <entry>
+       <parameter>resource_usage</parameter> was added.
+      </entry>
+     </row>
+    </tbody>
+   </tgroup>
+  </informaltable>
+ </refsect1>
+
  <refsect1 role="seealso">
   &reftitle.seealso;
   <para>