Simplify using helper methods in components

The `use_helpers` method was added in ViewComponent 3.8.0, and it's
included by default in all components since version 3.11.0.

Note we sometimes delegated the `can?` method to the controller instead
of the helpers, for no particularly reason. We're unifying that code as
well.

app/components/documents/document_component.rb

@@ -1,7 +1,7 @@
 class Documents::DocumentComponent < ApplicationComponent
   attr_reader :document, :show_destroy_link
   alias_method :show_destroy_link?, :show_destroy_link
-  delegate :can?, to: :helpers
+  use_helpers :can?
 
   def initialize(document, show_destroy_link: false)
     @document = document