Update psalm.xml

Author: JeroenDeDauw

psalm.xml

@@ -26,7 +26,6 @@
 		<directory name="../../vendor/wikimedia" />
 		<directory name="../../vendor/wikibase" />
 		<directory name="../../vendor/data-values" />
-		<directory name="../../extensions/Wikibase" />
 	</extraFiles>
 
 	<issueHandlers>