### Godot version

4.0 beta17

### System information

Windows10

### Issue description

call `"".split()`
Is there an infinite loop inside? Function does not return.

### Steps to reproduce

"".split()

### Minimal reproduction project

N/A
return (String::chr(p_chr) + p_str);
}
String &String::operator+=(const String &p_str) {
	const int lhs_len = length();
	if (lhs_len == 0) {
		*this = p_str;
		return *this;
	}
	const int rhs_len = p_str.length();
	if (rhs_len == 0) {
		return *this;
	}
	resize(lhs_len + rhs_len + 1);
	const char32_t *src = p_str.ptr();
	char32_t *dst = ptrw() + lhs_len;
	
	memcpy(dst, src, rhs_len * sizeof(char32_t));
	*(dst + rhs_len) = _null;
	return *this;
}
String &String::operator+=(const char *p_str) {