Add entitlement endpoints

Author: Exanlv

src/Discord/Endpoint.php

@@ -20,6 +20,10 @@ class Endpoint
 
     // GET
     public const APPLICATION_SKUS = 'applications/:application_id/skus';
+    // GET, POST
+    public const APPLICATION_ENTITLEMENTS = 'applications/:application_id/entitlements';
+    // DELETE
+    public const APPLICATION_ENTITLEMENT = 'applications/:application_id/entitlements/:entitlement_id';
     // GET, POST, PUT
     public const GLOBAL_APPLICATION_COMMANDS = 'applications/:application_id/commands';
     // GET, PATCH, DELETE