Drop support for classic autoloading

[gmcgibbon]

In c11faff we accidentally broke classic autoloading by referencing CsvCollectionBuilder. This made me remember that we should have removed support for this it several releases ago anyway.

Yes, we could instead make it clearer that we need to reference MaintenanceTasks::CsvCollectionBuilder in a fully qualified way, but I think since classic autoloading is deprecated both in Rails and the gem, we can just remove it now.

Closes #528

[adrianna-chang-shopify]

Thanks for following up on this Gannon 🙏 Seems fair to drop support at this point.

[etiennebarrie]

Wouldn't this be a breaking change though? I'm not ready to ship a 2.0 over this…

[adrianna-chang-shopify]

I do feel like we could get away with dropping support for a deprecated feature in a minor version release, but you're right that that's technically not good release behaviour. My concern is that we'll never feel ready to release a major version, and we'll have to keep reminding ourselves that these deprecations still exist and may continue to accidentally ship changes that are incompatible with the classic autoloader.

[gmcgibbon]

If we want to ship this with some other breaking changes, I'm alright with that. Maybe we can use milestones to coordinate releases in that case? If we don't have anything blocking the release, I think we should just do it. This has been warned about since 1.7.0 in 2fe9ab9.

[adrianna-chang-shopify]

Using a milestone to prep for a 2.0 release sounds like a great idea to me @gmcgibbon 👍 There are a couple of other deprecations we could remove:

• The old error_handler API
  

  maintenance_tasks/lib/maintenance_tasks.rb

  Lines 76 to 79 in 812d8e5

  	ActiveSupport::Deprecation.warn(
  	"MaintenanceTasks.error_handler should be a lambda that takes three "\
  	"arguments: error, task_context, and errored_element."
  	)

• Runner.new
  

  maintenance_tasks/app/models/maintenance_tasks/runner.rb

  Lines 9 to 14 in 812d8e5

  	def new
  	ActiveSupport::Deprecation.warn(
  	"Use Runner.run instead of Runner.new.run"
  	)
  	self
  	end

[gmcgibbon]

I can work on the other deprecations today. If there's any issues or PRs open that we should add to the milestone, please do so.

[etiennebarrie]

Sounds great! How do you feel about #612? Should the new refresh be part of 2.0 or should we ship a quick 1.10 with that and a few other things? v1.9.0...main

[adrianna-chang-shopify]

My vote would be to ship v1.10 with everything up to the deprecation removals, and then ship all the breaking changes together in 2.0.