Update scheduler SchedulerEvent namespace dependencies

Here's a patch which updates the namespaces from the scheduler module.

Thanks for the patch.

Is it possible to do that patch so that it works with both versions of scheduler?

If the patch fixes it with the latest version of scheduler, presumably it will break for people still using the previous version?
So to avoid releasing a new major version of advanced_scheduler I was wondering whether it was possible to make it work with both.

If not, we can roll this in to a new major version.

Namespace declaration for
"Drupal\scheduler\Event\SchedulerEvent"
to
"Drupal\scheduler\Event\SchedulerNodeEvents"

So updating the patch with the same

@nicrodgers I am not sure how to create a patch that would be valid for both the 2.1 and 2.2 version of the scheduler module, If someone can share steps on how to achieve that, I can update the current patch accordingly

Provided patches and MR for two approaches.

1. Dropping support for 1.x.
2. Adding support for both versions.

The implementation route is down to discretion of the maintainer.