Support before_enqueue for bulk delivery methods

[klaaspieter]

Pull Request

Summary:

Add support for canceling bulk delivery methods by raising in before_enqueue

Related Issue:

I didn't create one but I'll do so if necessary.

Description:

I was surprised to find that before_enqueue didn't work for bulk delivery methods. I also couldn't come up with a good reason why it shouldn't work.

Testing:

I added new tests to EventJobTest

Checklist:

• Code follows the project's coding standards
• Tests have been added or updated to cover the changes
• Documentation has been updated (if applicable)
• All existing tests pass
• Conforms to the contributing guidelines