### Godot version

4.0 dev Beta 10

### System information

MacBook Pro M1 Max

### Issue description

After I imported font.ttf file and move it from one folder to another under ://res godot suddenly crashed, and it still crashes after restart.

### Steps to reproduce

Import some font.ttf file and try to move into different folder

### Minimal reproduction project

N/A
FontAdvanced *fd = font_owner.get_or_null(p_font_rid);
	ERR_FAIL_COND_V(!fd, false);
	MutexLock lock(fd->mutex);
	return fd->fixed_size;
}
void TextServerAdvanced::_font_set_allow_system_fallback(const RID &p_font_rid, bool p_allow_system_fallback) {
	FontAdvanced *fd = font_owner.get_or_null(p_font_rid);
	ERR_FAIL_COND(!fd);
	MutexLock lock(fd->mutex);
	fd->allow_system_fallback = p_allow_system_fallback;
}
bool TextServerAdvanced::_font_is_allow_system_fallback(const RID &p_font_rid) const {
	FontAdvanced *fd = font_owner.get_or_null(p_font_rid);
	ERR_FAIL_COND_V(!fd, false);
	MutexLock lock(fd->mutex);
	return fd->allow_system_fallback;
}
void TextServerAdvanced::_font_set_force_autohinter(const RID &p_font_rid, bool p_force_autohinter) {
	FontAdvanced *fd = font_owner.get_or_null(p_font_rid);
	ERR_FAIL_COND(!fd);
	MutexLock lock(fd->mutex);
	if (fd->force_autohinter != p_force_autohinter) {
		_font_clear_cache(fd);
		fd->force_autohinter = p_force_autohinter;
	}
}
bool TextServerAdvanced::_font_is_force_autohinter(const RID &p_font_rid) const {