D9 - Migration::allRowsProcessed causes LogicException

Problem/Motivation

I'd like to use this module on a D9 site, but ran into less than a handful of issues that were preventing it from working.

1. Error: Call to undefined method Drupal\migrate\Plugin\Migration::get() in _migrate_queue_importer_check_dependencies() (line 137 of /var/www/html/public/modules/contrib/migrate_queue_importer/migrate_queue_importer.module)

2. LogicException: The database connection is not serializable.

3. Notice: Undefined index: ignore in Drupal\migrate_queue_importer\Plugin\QueueWorker\MigrateImportQueueWorker->processItem() (line 87 of modules/contrib/migrate_queue_importer/src/Plugin/QueueWorker/MigrateImportQueueWorker.php).

Steps to reproduce

* Drupal 9.2.6
* Migrate Tools 8.x-5.0
* Migrate Plus 8.x-5.1
* Migrate Queue Importer 8.x-1.x-dev

Proposed resolution

WORKAROUND, temporary.

1. Move to getMigrationDependencies() for retrieving dependencies.

2. Remove MigrationInterface::allRowsProcessed as a temporary workaround.

3. Explicitly set 'ignore' to FALSE instead of relying on the array key to not exist.

Remaining tasks

1. Determine if ['required'] key will always exist with all compatible versions of Migrate, potentially handle other responses.

2. Determine how to properly call this without getting the serialization error.

3. Explicitly set 'ignore' to FALSE instead of relying on the array key to not exist.

User interface changes

N/A

API changes

N/A

Data model changes

N/A