Disable foreign keys during `alter_table` for sqlite3 adapter

Unlike other databases, changing SQLite3 table definitions need to create a temporary table.
While changing table operations, the original table needs dropped which caused
`SQLite3::ConstraintException: FOREIGN KEY constraint failed` if the table is referenced by foreign keys.
This pull request disables foreign keys by `disable_referential_integrity`.

Also `disable_referential_integrity` method needs to execute `defer_foreign_keys = ON`
to defer re-enabling foreign keys until the transaction is committed.

https://www.sqlite.org/pragma.html#pragma_defer_foreign_keys

Fixes #31988

- This `defer_foreign_keys = ON` has been supported since SQLite 3.8.0
https://www.sqlite.org/releaselog/3_8_0.html and Rails 6 requires SQLite 3.8 #32923 now

- <Models>.reset_column_information added to address `ActiveModel::UnknownAttributeError`

```
Error:
ActiveRecord::Migration::ForeignKeyChangeColumnTest#test_change_column_of_parent_table:
ActiveModel::UnknownAttributeError: unknown attribute 'name' for ActiveRecord::Migration::ForeignKeyChangeColumnTest::Post.
```

1 files changed, 46 insertions, 0 deletions

diff --git a/activerecord/test/cases/migration/foreign_key_test.rb b/activerecord/test/cases/migration/foreign_key_test.rb
index 50f5696ad1..c471dd1106 100644
--- a/activerecord/test/cases/migration/foreign_key_test.rb
+++ b/activerecord/test/cases/migration/foreign_key_test.rb
@@ -19,6 +19,52 @@ if ActiveRecord::Base.connection.supports_foreign_keys_in_create?
           assert_equal "fk_name", fk.name unless current_adapter?(:SQLite3Adapter)
         end
       end
+
+      class ForeignKeyChangeColumnTest < ActiveRecord::TestCase
+        self.use_transactional_tests = false
+
+        class Rocket < ActiveRecord::Base
+          has_many :astronauts
+        end
+
+        class Astronaut < ActiveRecord::Base
+          belongs_to :rocket
+        end
+
+        setup do
+          @connection = ActiveRecord::Base.connection
+          @connection.create_table "rockets", force: true do |t|
+            t.string :name
+          end
+
+          @connection.create_table "astronauts", force: true do |t|
+            t.string :name
+            t.references :rocket, foreign_key: true
+          end
+          Rocket.reset_column_information
+          Astronaut.reset_column_information
+        end
+
+        teardown do
+          @connection.drop_table "astronauts", if_exists: true
+          @connection.drop_table "rockets", if_exists: true
+          Rocket.reset_column_information
+          Astronaut.reset_column_information
+        end
+
+        def test_change_column_of_parent_table
+          foreign_keys = ActiveRecord::Base.connection.foreign_keys("astronauts")
+          rocket = Rocket.create!(name: "myrocket")
+          rocket.astronauts << Astronaut.create!
+
+          @connection.change_column_null :rockets, :name, false
+
+          fk = foreign_keys.first
+          assert_equal "myrocket", Rocket.first.name
+          assert_equal "astronauts", fk.from_table
+          assert_equal "rockets", fk.to_table
+        end
+      end
     end
   end
 end