Library item form should be altered with hook_form_BASE_FORM_ID_alter

The library entity form has changed the way how it defines its form ID.

The form ID is now build like:

  public function getFormId() {
    // If the entity is not new, add the entity id. This will allow having more
    // than one form open when editing a library item within another.
    // To alter this form use hook_form_BASE_FORM_ID_alter.
    if ($this->entity->id()) {
      return 'paragraphs_library_item_edit_form_' . $this->entity->id();
    }
    return 'paragraphs_library_item_edit_form';
  }

After this change, altering the Library Item form will be made with the hook hook_form_BASE_FORM_ID_alter.

Before

/**
 * Implements hook_form_FORM_ID_alter().
 */
function paragraphs_library_form_paragraphs_library_item_edit_form_alter(&$form, FormStateInterface $form_state, $form_id) {
  $library_item = $form_state->getFormObject()->getEntity();
  // Your code here.
}

After

/**
 * Implements hook_form_BASE_FORM_ID_alter().
 */
function paragraphs_library_form_paragraphs_library_item_form_alter(&$form, FormStateInterface $form_state, $form_id) {
  $library_item = $form_state->getFormObject()->getEntity();
  // Your code here.
}