Make CodeSniffer ignore unnecessary file extensions

Author: R4356th

phpcs.xml

@@ -10,6 +10,6 @@
 	</rule>
 	<file>.</file>
 	<arg name="bootstrap" value="./vendor/mediawiki/mediawiki-codesniffer/utils/bootstrap-ci.php"/>
-	<arg name="extensions" value="php,php5,inc"/>
+	<arg name="extensions" value="php"/>
 	<arg name="encoding" value="UTF-8"/>
 </ruleset>