### 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.
int from = 0;
	int len = length();
	while (true) {
		int end = find(p_splitter, from);
		if (end < 0) {
			end = len;
		}
		if (p_allow_empty || (end > from)) {
			ret.push_back(::to_float(&get_data()[from]));
		}
		if (end == len) {
			break;
		}
		from = end + p_splitter.length();
	}
	return ret;
}
Vector<float> ::split_floats_mk(const Vector<> &p_splitters, bool p_allow_empty) const {
	Vector<float> ret;
	int from = 0;
	int len = length();
	while (true) {
		int idx;
		int end = findmk(p_splitters, from, &idx);
		int spl_len = 1;
		if (end < 0) {
			end = len;
		} else {
			spl_len = p_splitters[idx].length();
		}