AddressDefaultFormatter must implement \Drupal\Core\Security\TrustedCallbackInterface as of Drupal 8.8

Problem/Motivation

Render #post_render callbacks must be methods of a class that implements \Drupal\Core\Security\TrustedCallbackInterface or be an anonymous function. The callback was Drupal\address\Plugin\Field\FieldFormatter\AddressDefaultFormatter::postRender. Support for this callback implementation is deprecated in 8.8.0 and will be removed in Drupal 9.0.0. See https://www.drupal.org/node/2966725

Proposed resolution

Unfortunatly, this interface doesn't exist until 8.8, so we need a little workaround to be compatible with 8.6 and 8.7 at the same time.

Remaining tasks

User interface changes

API changes

Data model changes

Release notes snippet