Fix the problems #6

Fix the problems https://www.drupal.org/project/projectapplications/issues/3608209#commen...

1. FILE: README.md

The README file is missing the required sections - Requirements and Configuration.

2. FILE: src/Plugin/Field/FieldFormatter/SimpleParallaxFieldFormatter.php

 * @FieldFormatter(
 *   id = "simple_parallax_field_formatter",
 *   label = @Translation("Simple Parallax"),
 *   field_types = {
 *     "entity_reference",
 *     "image"
 *   }
 * )

Projects that are compatible with Drupal 10 or higher versions should use attributes instead of annotations.