### 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
found = false;
					break;
				}
			}
			if (found) {
				return i;
			}
		}
	}
	return -1;
}
int String::find_char(const char32_t &p_char, int p_from) const {
	return _cowdata.find(p_char, p_from);
}
int String::findmk(const Vector<String> &p_keys, int p_from, int *r_key) const {
	if (p_from < 0) {
		return -1;
	}
	if (p_keys.size() == 0) {
		return -1;
	}
	
	const String *keys = &p_keys[0];
	int key_count = p_keys.size();
	int len = length();
	if (len == 0) {
		return -1; 
	}
	const char32_t *src = get_data();
	for (int i = p_from; i < len; i++) {