The "--execute-dependencies" option is currently broken due to the deprecation of the "get('requirements')" method

The https://www.drupal.org/project/migrate_tools/issues/3024399#comment-1333... commit broke the --execute-dependencies option.

$migration->get('requirements');

is not the same as

$definition = $migration->getPluginDefinition();
$required_migrations = $definition['requirements'] ?? [];

The requirements property is built and set in the \Drupal\migrate\Plugin\MigrationPluginManager::createInstances function.

Trying to follow the reason behind the change leads to this.

Since there's no interface method available to retrieve that property, the only viable solution is to use MigrationInterface::getMigrationDependencies(), and build a similar list of dependency ids.