### 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 ::num(p_val);
}
 rtoss(double p_val) {
	return ::num_scientific(p_val);
}
// Right-pad with a character.
 ::rpad(int min_length, const  &character) const {
	 s = *this;
	int padding = min_length - s.length();
	if (padding > 0) {
		s += character.repeat(padding);
	}
	return s;
}
// Left-pad with a character.
 ::lpad(int min_length, const  &character) const {
	 s = *this;
	int padding = min_length - s.length();
	if (padding > 0) {
		s = character.repeat(padding) + s;
	}
	return s;
}
// sprintf is implemented in GDScript via:
//   "fish %s pie" % "frog"
//   "fish %s %d pie" % ["frog", 12]
// In case of an error, the string returned is the error description and "error" is true.
 ::sprintf(const Array &values, bool *error) const {