iss1171 - Fix order.

Author: EJMFarrow

tests/questiontype_test.php

@@ -270,8 +270,8 @@ public function test_xml_export(): void {
     <logicsymbol>lang</logicsymbol>
     <matrixparens>[</matrixparens>
     <isbroken>0</isbroken>
-    <metadata>{}</metadata>
     <prescribedmetadata></prescribedmetadata>
+    <metadata>{}</metadata>
     <variantsselectionseed></variantsselectionseed>
     <input>
       <name>ans1</name>