Replace alias_attribute with define_method

Rails 7.1 lazily defines methods.  These are associations, not attributes, so we can't
use alias_attribute.

Fixes the following error with Rails 7.1:

Association named 'provisioning_manager' was not found on CustomizationScript

app/models/mixins/deprecation_mixin.rb

@@ -22,7 +22,9 @@ def deprecate_attribute(old_attribute, new_attribute, type:)
     end
 
     def deprecate_attribute_methods(old_attribute, new_attribute)
-      alias_attribute old_attribute, new_attribute
+      define_method(old_attribute) { self.send(new_attribute) }
+      define_method("#{old_attribute}=") { |object| self.send("#{new_attribute}=", object) }
+      define_method("#{old_attribute}?") { self.send("#{new_attribute}?") }
       ["", "=", "?"].each { |suffix| Vmdb::Deprecation.deprecate_methods(self, "#{old_attribute}#{suffix}" => "#{new_attribute}#{suffix}") }
     end
   end

spec/models/mixins/deprecation_mixin_spec.rb

@@ -1,16 +1,4 @@
 RSpec.describe DeprecationMixin do
-  # Host.deprecate_attribute :address, :hostname
-  context ".arel_table" do
-    # this is defining an alias
-    # it is not typical for aliases to work through arel_table
-    # may need to get rid of this in the future
-    it "works for deprecate_attribute columns" do
-      expect(Host.attribute_supported_by_sql?(:address)).to eq(true)
-      expect(Host.arel_table[:address]).to_not be_nil
-      expect(Host.arel_table[:address].name).to eq("hostname") # typically this is a symbol. not perfect but it works
-    end
-  end
-
   # Host.deprecate_attribute :address, :hostname
   context ".visible_attribute_names" do
     it "hides deprecate_attribute columns" do