### Godot version

v4.1.stable.official [970459615]

### System information

Windows 11

### Issue description

Using `String::pad_zeros` on a string containing digits with greater length than the argument `digits` raises the error `Parameter count should be a positive number.` of `String::repeat`, because it is called with a negative parameter.
(Actually this error is not 100% correct, it should be non-negative)

4.0 Code:
https://github.com/godotengine/godot/blob/c8e0bd50c57de91c061866db1de407f2e7a74acd/core/string/ustring.cpp#L4127-L4155

Example: `"2023".pad_zeros(2)`
`begin == 0`
`end == 4`
`end - begin < p_digits == false` => No "0" is inserted, the string is returned unchanged.

4.1 Code:
https://github.com/godotengine/godot/blob/ce5c6151fc498b39fe0c188045a4685e0f627854/core/string/ustring.cpp#L4266-L4290

Example: `"2023".pad_zeros(2)`
`begin == 0`
`end == 4`
`zeros_to_add == 2 - (4 - 0) == -2`
=> `s.insert(0, String("0").repeat(-2))` is called => Error.

I don't know why this was changed, but I think ensuring that `zeros_to_add > 0` should be ensured internally and not by the user. If this condition is not fullfilled the string should be returned unchanged as in the 4.0 implementation.

### Steps to reproduce

Try my above mentioned example in 4.0 and 4.1

### Minimal reproduction project

Not necessary.
return built_in_strtod<char>(p_str);
}
double ::to_float(const char32_t *p_str, const char32_t **r_end) {
	return built_in_strtod<char32_t>(p_str, (char32_t **)r_end);
}
double ::to_float(const wchar_t *p_str, const wchar_t **r_end) {
	return built_in_strtod<wchar_t>(p_str, (wchar_t **)r_end);
}
uint32_t ::num_characters(int64_t p_int) {
	int r = 1;
	if (p_int < 0) {
		r += 1;
		if (p_int == INT64_MIN) {
			p_int = INT64_MAX;
		} else {
			p_int = -p_int;
		}
	}
	while (p_int >= 10) {
		p_int /= 10;
		r++;
	}
	return r;
}
int64_t ::to_int(const char32_t *p_str, int p_len, bool p_clamp) {