Resolve #3464720 "Drupal 11"

Add Drupal 11 to core_version_requirement. Closes #3464720.

src/Plugin/Field/FieldWidget/YearOnlyDefaultWidget.php

@@ -61,15 +61,25 @@ class YearOnlyDefaultWidget extends WidgetBase implements WidgetInterface {
    * {@inheritdoc}
    */
   public function formElement(FieldItemListInterface $items, $delta, array $element, array &$form, FormStateInterface $form_state) {
-    $field_settings = $this->getFieldSettings();
 
-    if ($field_settings['yearonly_to'] == 'now') {
-      $field_settings['yearonly_to'] = date('Y');
+    $yearonly_from = $this->getFieldSetting('yearonly_from') ?: 0;
+    $yearonly_to = $this->getFieldSetting('yearonly_to') ?: 0;
+
+    if ($yearonly_to == 'now') {
+      $yearonly_to = date('Y');
+    }
+
+    $yearonly_from = (int) $yearonly_from;
+    $yearonly_to = (int) $yearonly_to;
+
+    if($yearonly_from > $yearonly_to)
+    {
+      $yearonly_from = $yearonly_to;
     }
 
     $options = array_combine(
-      range($field_settings['yearonly_from'], $field_settings['yearonly_to']),
-      range($field_settings['yearonly_from'], $field_settings['yearonly_to'])
+      range($yearonly_from, $yearonly_to),
+      range($yearonly_from, $yearonly_to)
     );
 
     if ($this->getSetting('sort_order') == 'desc') {