docs(model): fix missing comma in scope example (#8297)

lib/model.js

@@ -1295,7 +1295,7 @@ class Model {
    *
    * To invoke scope functions you can do:
    * ```js
-   * Model.scope({ method: ['complexFunction' 'dan@sequelize.com', 42]}).findAll()
+   * Model.scope({ method: ['complexFunction', 'dan@sequelize.com', 42]}).findAll()
    * // WHERE email like 'dan@sequelize.com%' AND access_level >= 42
    * ```
    *