Fix typo in sample configuration

Add missing comma in configuration example.

README.md

@@ -42,7 +42,7 @@ Mfc\OAuth2\ResourceServer\Registry::addServer(
             'gitlabAdminUserLevel' => \Mfc\OAuth2\ResourceServer\GitLab::USER_LEVEL_DEVELOPER, // User level at which the user will be given admin permissions
             'gitlabDefaultGroups'  => '0', // Groups to assign to the User (comma separated list possible)
             'gitlabUserOption'     => 0, // UserConfig
-            'blockExternalUser'    => false // Blocks users with flag external from access the backend
+            'blockExternalUser'    => false, // Blocks users with flag external from access the backend
             'projectName'          => 'your/repo', // the repository from which user information is fetched
         ],
     ]