### Godot version

v4.0.beta.custom_build [13f0158]

### System information

Windows 10

### Issue description

When doing operations (`begin_complex_operation` and `end_complex_operation`) with multiple selections in TextEdit, some of these selections don't revert upon undo. This behavior is affects some of script editor's operations, like duplicate selection and delete lines.

### Steps to reproduce

Open script editor, make multiple selections. Keep in mind what you have selected. Do duplicate selection (ctrl+shift+D). Undo (ctrl+Z). Compare the result to what you remember.

### Minimal reproduction project

N/A
CHECK(text_edit->get_text() == "thissome text\nfor selection");
			text_edit->undo();
			CHECK(text_edit->has_selection());
			CHECK(text_edit->get_text() == "this is some text\nfor selection");
			CHECK(text_edit->get_caret_line() == 0);
			CHECK(text_edit->get_caret_column() == 8);
			text_edit->redo();
			CHECK_FALSE(text_edit->has_selection());
			CHECK(text_edit->get_text() == "thissome text\nfor selection");
			CHECK(text_edit->get_caret_line() == 0);
			CHECK(text_edit->get_caret_column() == 4);
			text_edit->undo();
			CHECK(text_edit->has_selection());
			CHECK(text_edit->get_text() == "this is some text\nfor selection");
			CHECK(text_edit->get_caret_line() == 0);
			CHECK(text_edit->get_caret_column() == 8);
			text_edit->set_editable(false);
			text_edit->delete_selection();
			text_edit->set_editable(false);
			CHECK_FALSE(text_edit->has_selection());
			CHECK(text_edit->get_text() == "thissome text\nfor selection");
			text_edit->undo();
			CHECK_FALSE(text_edit->has_selection());
			CHECK(text_edit->get_text() == "thissome text\nfor selection");
		}
		
		SUBCASE("[TextEdit] text drag") {
			TextEdit *target_text_edit = memnew(TextEdit);
			SceneTree::get_singleton()->get_root()->add_child(target_text_edit);
			target_text_edit->set_size(Size2(200, 200));