Composer: Add PHPCSUtils as required dependency

VIPCS makes use of PHPCSUtils directly (such as for MessageHelper), so it should be marked as such in the Composer config.

Author: GaryJones

composer.json

@@ -18,6 +18,7 @@
 	"require": {
 		"php": ">=5.4",
 		"dealerdirect/phpcodesniffer-composer-installer": "^0.4.1 || ^0.5 || ^0.6.2 || ^0.7 || ^1.0",
+		"phpcsstandards/phpcsutils": "^1.0",
 		"sirbrillig/phpcs-variable-analysis": "^2.11.1",
 		"squizlabs/php_codesniffer": "^3.7.1",
 		"wp-coding-standards/wpcs": "^2.3"