- Action Mailer delivery job should modify their `perform` method
signature in order to receive the new payload that Action Mailer
sends.
Before:
```ruby
def perform(mailer, mail_method, delivery_method, *args)
end
```
After:
```ruby
def perform(mailer, mail_method, delivery_method, args:)
end
```
This new behaviour was introduced couple years ago in a attempt to
get rid of the necessity to have a different job for paramterized
mailers. A deprecation was introduced for custom jobs inheriting
from `ActionMailer::DeliveryJob` but for jobs that didn't it went
unnoticed.
The deprecated behaviour was supposed to be removed in Rails 6.1
but we couldn't and it got reverted https://github.com/rails/rails/pull/39257
This reverts commit 0f9249c93f.
Reverted because this wasn't warning in custom jobs and therefore
applications may have not seen the deprecation. We'll need to fix the
deprecation to warn for custom jobs so that applications can migrate.
Edouard CHIN