build: Updating mediawiki/mediawiki-codesniffer to 23.0.0

And updating CoC link to use Special:MyLanguage (T202047).

Change-Id: Ic41ecd85fb17f509546d8ebf4af407d549f8f540

.phpcs.xml

@@ -1,6 +1,6 @@
 <?xml version="1.0"?>
 <ruleset>
-	<rule ref="./vendor/mediawiki/mediawiki-codesniffer/MediaWiki"/>
+	<rule ref="./vendor/mediawiki/mediawiki-codesniffer/MediaWiki" />
 	<file>.</file>
 	<arg name="bootstrap" value="./vendor/mediawiki/mediawiki-codesniffer/utils/bootstrap-ci.php"/>
 	<arg name="extensions" value="php,php5,inc"/>

CODE_OF_CONDUCT.md

@@ -1 +1 @@
-The development of this software is covered by a [Code of Conduct](https://www.mediawiki.org/wiki/Code_of_Conduct).
+The development of this software is covered by a [Code of Conduct](https://www.mediawiki.org/wiki/Special:MyLanguage/Code_of_Conduct).

composer.json

@@ -1,7 +1,7 @@
 {
 	"require-dev": {
 		"jakub-onderka/php-parallel-lint": "1.0.0",
-		"mediawiki/mediawiki-codesniffer": "22.0.0",
+		"mediawiki/mediawiki-codesniffer": "23.0.0",
 		"jakub-onderka/php-console-highlighter": "0.3.2",
 		"mediawiki/minus-x": "0.3.1"
 	},