Add support for ActiveJob 7.1

[shashankmehra]

Breaking changes addressed

Action Mailer exception

In ActionMailer 7.1+ the following call throws an exception:

ActionMailer::MailDeliveryJob.new.queue_name

This is because MailDeliveryJob accepts the Mailer as the first argument and uses the mailer dynamically to get the queue name using deliver_later_queue_name. So, calling queue_name without passing the arguments throws an exception.

The only way to pass arguments is to call perform_later - which we cannot do just to get queue_name.

This was solved by adding special handling for MailDeliveryJob. We use deliver_later_queue_name from the mailer itself to get the queue name - same as MailDeliveryJob.

Checklist

• Make sure existing tests pass
• Write tests for expanded functionality of Mailer specific queue
• Update Changelog