Drop virtual_delegates_to_define

By defining the ruby method up front and registering the arel and uses,
the code can use the new simplified virtual attribute registration process.

Care does need to go into ensuring that virtual_delegate_arel does not access the schema

Do note, we are not passing options into virtual_attributes, which get passed to Type.lookup.
This was not working for virtual_delegates before.
TBH/ I don't know if we use this in the type lookup. Maybe these are be used when using array types?
It looks like rails uses the options for the matchers. It wasn't fully clear for me.

Author: kbrock

lib/active_record/virtual_attributes.rb

@@ -98,10 +98,6 @@ def load_schema!
 
           define_virtual_attribute(name, type)
         end
-
-        virtual_delegates_to_define.each do |method_name, (method, options)|
-          define_virtual_delegate(method_name, method, options)
-        end
       end
 
       def define_virtual_attribute(name, cast_type)

lib/active_record/virtual_attributes/virtual_delegates.rb

@@ -9,10 +9,6 @@ module VirtualAttributes
     module VirtualDelegates
       extend ActiveSupport::Concern
 
-      included do
-        class_attribute :virtual_delegates_to_define, :instance_accessor => false, :default => {}
-      end
-
       module ClassMethods
         #
         # Definition
@@ -37,32 +33,12 @@ def virtual_delegate(*methods, to:, type:, prefix: nil, allow_nil: nil, default:
             end
 
             define_delegate(method_name, method, :to => to, :allow_nil => allow_nil, :default => default)
-            define_virtual_include(method_name, uses || to)
-            define_virtual_arel(method_name, virtual_delegate_arel(method, to_ref))
-            self.virtual_delegates_to_define =
-              virtual_delegates_to_define.merge(method_name.to_s => [method, options.merge(:to => to, :type => type)])
+            virtual_attribute(method_name, type, :uses => (uses || to), :arel => virtual_delegate_arel(method, to_ref), **options)
           end
         end
 
         private
 
-        # define virtual_attribute for delegates
-        #
-        # this is called at schema load time (and not at class definition time)
-        #
-        # @param  method_name [Symbol] name of the attribute on the source class to be defined
-        # @param  col [Symbol] name of the attribute on the associated class to be referenced
-        # @option options :to [Symbol] name of the association from the source class to be referenced
-        # @option options :arel [Proc] (optional and not common)
-        # @option options :uses [Array|Symbol|Hash] sql includes hash. (default: to)
-        # @option options :type [Symbol|ActiveModel::Type::Value] type for the attribute
-        def define_virtual_delegate(method_name, col, options)
-          type = options[:type]
-          type = ActiveRecord::Type.lookup(type) if type.kind_of?(Symbol)
-
-          define_virtual_attribute(method_name, type)
-        end
-
         # see activesupport module/delegation.rb
         # rubocop:disable Style/TernaryParentheses
         def define_delegate(method_name, method, to: nil, allow_nil: nil, default: nil) # rubocop:disable Naming/MethodParameterName