### Godot version

4.x

### System information

Windows 10

### Issue description

The `Search Result` panel is not correctly updated when changing the theme.

https://user-images.githubusercontent.com/66004280/208964493-d0423b78-3418-44c9-95ed-822fd34c4720.mp4



### Steps to reproduce

1. Search something
2. Change the theme

### Minimal reproduction project

--
_pattern = p_pattern;
}
void FindInFiles::set_whole_words(bool p_whole_word) {
	_whole_words = p_whole_word;
}
void FindInFiles::set_match_case(bool p_match_case) {
	_match_case = p_match_case;
}
void FindInFiles::set_folder(String folder) {
	_root_dir = folder;
}
void FindInFiles::set_filter(const HashSet<String> &exts) {
	_extension_filter = exts;
}
void FindInFiles::_notification(int p_what) {