Add test cases for optimistic locking

Add test to ensure that locking_column cannot be updated explicitly.

Add test to prevent regression on creating new object with
explicit value locking_column.

Related to #28318

activerecord/test/cases/locking_test.rb

@@ -167,6 +167,12 @@ def test_lock_new_when_explicitly_passing_nil
     assert_equal 0, p1.lock_version
   end
 
+  def test_lock_new_when_explicitly_passing_value
+    p1 = Person.new(first_name: "Douglas Adams", lock_version: 42)
+    p1.save!
+    assert_equal 42, p1.lock_version
+  end
+
   def test_touch_existing_lock
     p1 = Person.find(1)
     assert_equal 0, p1.lock_version
@@ -186,6 +192,19 @@ def test_touch_stale_object
     end
   end
 
+  def test_explicit_update_lock_column_raise_error
+    person = Person.find(1)
+
+    assert_raises(ActiveRecord::StaleObjectError) do
+      person.first_name = "Douglas Adams"
+      person.lock_version = 42
+
+      assert person.lock_version_changed?
+
+      person.save
+    end
+  end
+
   def test_lock_column_name_existing
     t1 = LegacyThing.find(1)
     t2 = LegacyThing.find(1)