McryptAES128Encryption::checkDependencies() type hints incompatible with EncryptionMethodInterface — PHP Fatal error on config import

Problem/Motivation

When using TFA 8.x-1.12 alongside Encrypt 8.x-3.3 on PHP 8.0+, a PHP Fatal error is thrown during config import (and anywhere Drupal loads the plugin registry):

PHP Fatal error: Declaration of Drupal\tfa\Plugin\EncryptionMethod\McryptAES128Encryption::checkDependencies(?string $text = null, ?string $key = null) must be compatible with
  Drupal\encrypt\EncryptionMethodInterface::checkDependencies($text = null, $key = null) in .../tfa/src/Plugin/EncryptionMethod/McryptAES128Encryption.php on line 150

Encrypt 8.x-3.3 added #[\SensitiveParameter] attributes to EncryptionMethodInterface::checkDependencies() while leaving the parameters untyped:

public function checkDependencies(#[\SensitiveParameter] $text = NULL, #[\SensitiveParameter] $key = NULL);

McryptAES128Encryption::checkDependencies() declares ?string type hints, which narrows the accepted types relative to what the interface declares. In PHP 8.0+, an implementing class cannot restrict
parameter types beyond the interface definition.

Steps to reproduce

1. Install TFA 8.x-1.12 and Encrypt 8.x-3.3 on PHP 8.0+.
2. Run drush cim or visit any page that triggers plugin autoloading.

Proposed resolution

Remove the ?string type hints from McryptAES128Encryption::checkDependencies() so the signature matches the interface:

public function checkDependencies($text = NULL, $key = NULL) {

Remaining tasks

• Review and commit patch.

User interface changes

None.

API changes

None.

Data model changes

None.