Update references to the Composer plugin

The Composer plugin has a new home.

Ref: PHPCSStandards/composer-installer#146

CHANGELOG.md

@@ -41,7 +41,7 @@ Props: jrfnl, rebeccahum, kevinfodness, GaryJones.
 
 ** There is a minor breaking change in the ProperEscapingFunction sniff from PR [#624](https://github.com/Automattic/VIP-Coding-Standards/pull/624). The `escaping_function` property can no longer be overruled via custom rulesets. Please remove any usages of the property in custom rulesets.
 
-** Composer now requires the [phpcodesniffer-composer-installer](https://github.com/Dealerdirect/phpcodesniffer-composer-installer) plugin per [#583](https://github.com/Automattic/VIP-Coding-Standards/pull/583). Note: If you either include it in the "require-dev" of your `composer.json`, use another Composer PHPCS plugin, or run bash commands to register PHPCS standards, please remove it from those sources to prevent interferences or version constraint conflicts.
+** Composer now requires the [phpcodesniffer-composer-installer](https://github.com/PHPCSStandards/composer-installer) plugin per [#583](https://github.com/Automattic/VIP-Coding-Standards/pull/583). Note: If you either include it in the "require-dev" of your `composer.json`, use another Composer PHPCS plugin, or run bash commands to register PHPCS standards, please remove it from those sources to prevent interferences or version constraint conflicts.
 
 ### Added
 - [#581](https://github.com/Automattic/VIP-Coding-Standards/pull/581): AlwaysReturnInFilter: flag abstract methods for manual inspection.

README.md

@@ -38,7 +38,7 @@ This will install the latest compatible versions of PHPCS, WPCS and VariableAnal
 
 Please refer to the [installation instructions for installing PHP_CodeSniffer for WordPress.com VIP](https://docs.wpvip.com/how-tos/code-review/php_codesniffer/) for more details.
 
-As of VIPCS version 2.3.0, there is no need to `require` the [PHP_CodeSniffer Standards Composer Installer Plugin](https://github.com/Dealerdirect/phpcodesniffer-composer-installer) anymore as it is now a requirement of VIPCS itself. Permission to run the plugin will still need to be granted though when using Composer 2.2 or higher.
+As of VIPCS version 2.3.0, there is no need to `require` the [PHP_CodeSniffer Standards Composer Installer Plugin](https://github.com/PHPCSStandards/composer-installer) anymore as it is now a requirement of VIPCS itself. Permission to run the plugin will still need to be granted though when using Composer 2.2 or higher.
 
 ## Contribution