### Godot version

4.0 beta 15

### System information

Windows 10

### Issue description

It happened with both Google IME and MS-IME, and there was no problem until Beta14.
When typing Japanese characters, it is common to select a character from the suggestion window and then start typing the next character before confirming.
In this case, uncommitted characters are forcibly committed, and input of the next character begins.

**↓Beta15**

https://user-images.githubusercontent.com/186786/214753450-b493cca6-2644-4b3d-8cd2-660565cc3547.mp4

**↓Beta14**

https://user-images.githubusercontent.com/186786/214755127-dde819cc-4d63-403a-99b0-09821671f74e.mp4



### Steps to reproduce

It happened with both Google IME and MS-IME in beta15

### Minimal reproduction project

It is project independent and happens in the editor.
_push_current_op();
	if (complex_operation_count == 0) {
		next_operation_is_complex = true;
		current_op.start_carets = carets;
	}
	complex_operation_count++;
}
void TextEdit::end_complex_operation() {
	_push_current_op();
	complex_operation_count = MAX(complex_operation_count - 1, 0);
	if (complex_operation_count > 0) {
		return;
	}
	ERR_FAIL_COND(undo_stack.size() == 0);
	undo_stack.back()->get().end_carets = carets;
	if (undo_stack.back()->get().chain_forward) {
		undo_stack.back()->get().chain_forward = false;
		return;
	}
	undo_stack.back()->get().chain_backward = true;
}
bool TextEdit::has_undo() const {
	if (undo_stack_pos == nullptr) {
		int pending = current_op.type == TextOperation::TYPE_NONE ? 0 : 1;
		return undo_stack.size() + pending > 0;
	}
	return undo_stack_pos != undo_stack.front();
}
bool TextEdit::has_redo() const {