Move the code that send emails into a service class

Any other change like ✨ Implement queue mechanism Needs work must wait this issue is fixed. I am working on this and already changing the module code (adding two new classes).

The changes I am introducing are slightly different from the changes introduced from the current patch in ✨ Implement queue mechanism Needs work .

I will commit the code between 3 hours, after verifying the changes are correct and the BC layer is in place.

apaderno → credited cgoffin → .

apaderno → credited dave.mentens → .

I would like to understand how much sites using this module are still on Drupal 9, and when they will upgrade to Drupal 10. This would be information useful to decide about back-ports, although the module has never had a stable release. (That means the project API could still be changed and the back-ports are still possible.)

Automatically closed - issue fixed for 2 weeks with no activity.