build: Updating mediawiki/mediawiki-codesniffer to 0.12.0

The following sniffs are failing and were disabled:
* MediaWiki.Files.ClassMatchesFilename.NotMatch

Change-Id: Ibc09672315c2dfcfc97311c3c86359e6ad443d14
diff --git a/composer.json b/composer.json
index a4c40a7..7c63cad 100644
--- a/composer.json
+++ b/composer.json
@@ -1,7 +1,7 @@
 {
 	"require-dev": {
 		"jakub-onderka/php-parallel-lint": "0.9.2",
-		"mediawiki/mediawiki-codesniffer": "0.11.0",
+		"mediawiki/mediawiki-codesniffer": "0.12.0",
 		"jakub-onderka/php-console-highlighter": "0.3.2"
 	},
 	"scripts": {
diff --git a/phpcs.xml b/phpcs.xml
index 6cac084..41cdf90 100644
--- a/phpcs.xml
+++ b/phpcs.xml
@@ -2,6 +2,7 @@
 <ruleset>
 	<rule ref="./vendor/mediawiki/mediawiki-codesniffer/MediaWiki">
 		<exclude name="MediaWiki.Commenting.FunctionComment.MissingDocumentationPublic" />
+		<exclude name="MediaWiki.Files.ClassMatchesFilename.NotMatch" />
 		<exclude name="MediaWiki.WhiteSpace.SpaceBeforeSingleLineComment.NewLineComment" />
 	</rule>
 	<file>.</file>