Drupal 9 Readiness

Add core_version_requirement: ^8 || ^9 to account_settings_tab.info.yml to designate that the module is compatible with Drupal 9. See https://drupal.org/node/3070687.

Rector 0.8.x-dev@8896f0a
Config file: rector.yml

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1 file with changes
===================

1) web/modules/contrib/user_private_fields/user_private_fields.module

    ---------- begin diff ----------
--- Original
+++ New
@@ -91,7 +91,7 @@
  */

 function user_private_fields_form_user_form_alter(&$form, FormStateInterface $form_state, $form_id) {
-  $entity_field_definitions = \Drupal::entityManager()
+  $entity_field_definitions = \Drupal::service('entity_field.manager')
     ->getFieldDefinitions('user', 'user');
   foreach ($entity_field_definitions as $field_key => $field_value) {
     $selected_field = strpos($field_key, 'field');
    ----------- end diff -----------