Fix #50499: instantiation of inherited classes when quering

Previously, querying from the base class resulted in an object of the inherited type,
with 'ignored_columns' included in the 'attributes' method.

This behavior was inconsistent, as it did not occur when querying directly from the inherited class.
This fix ensures consistent behavior in class instantiation during queries.

activerecord/lib/active_record/inheritance.rb

@@ -282,6 +282,11 @@ def set_base_class # :nodoc:
         end
 
       private
+        def instantiate_instance_of(klass, attributes, column_types = {}, &block)
+          attributes.except!(*klass.ignored_columns) if using_single_table_inheritance?(attributes)
+          super
+        end
+
         def inherited(subclass)
           super
           subclass.set_base_class

activerecord/test/cases/inheritance_test.rb

@@ -578,6 +578,7 @@ class Startup < Company
   end
 
   class Empire < Company
+    self.ignored_columns = [:description]
   end
 
   def test_inheritance_new_with_subclass_as_default
@@ -589,6 +590,13 @@ def test_inheritance_new_with_subclass_as_default
     assert_equal "InheritanceAttributeTest::Empire", empire.type
     assert_instance_of Empire, empire
   end
+
+  def test_when_quering_from_base_class_instantiate_subclass_without_ignored_columns
+    empire = Empire.create!(name: "Empire")
+    empire_called_from_sti = Company.find(empire.id)
+    assert_not_includes(empire_called_from_sti.attributes.keys, "description")
+    assert_equal(empire_called_from_sti.attributes.keys.size, Empire.column_names.size)
+  end
 end
 
 class InheritanceAttributeMappingTest < ActiveRecord::TestCase