Add support for PHP attributes for EncryptionMethod plugins

I added an initial implementation of this.

I rewrote the comments from Annotation/EncryptionMethod.php.

I need to check about the type for $description, so marking as "Needs work".

This changes the default value of $description from an empty string to NULL. For the reasoning behind this, see my question and answer on Drupal Answers: https://drupal.stackexchange.com/questions/320851/converting-an-annotati...

Setting this to "Needs review". The tests are failing, but I fixed phpcs here: 📌 phpcs september 2024 update Active

Looks good. Thanks!

Automatically closed - issue fixed for 2 weeks with no activity.