Add Symfony Deprecation Contracts package

- Created CHANGELOG.md to maintain version history.
- Added README.md with usage instructions for the trigger_deprecation() function.
- Initialized composer.json for the Symfony Deprecation Contracts library, specifying dependencies and autoloading.

modules/pshowsso/config.php

@@ -11,7 +11,5 @@
  * @copyright Since 2014 PrestaShow.pl
  * @license   https://prestashow.pl/license
  */
-require_once dirname(__FILE__) . '/vendor/autoload.php';
 
-$scopedPrefix = include dirname(__FILE__) . '/vendor/scoped-prefix.php';
-class_alias($scopedPrefix . '\League\OAuth2\Client\Grant\AuthorizationCode', 'League\OAuth2\Client\Grant\AuthorizationCode');
+require_once __DIR__ . '/vendor/autoload.php';