### 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.
ERR_FAIL_COND_V_MSG(length() % 2 != 0, Vector<uint8_t>(), "Hexadecimal string of uneven length.");
#define HEX_TO_BYTE(m_output, m_index)                                                                                   \
	uint8_t m_output;                                                                                                    \
	c = operator[](m_index);                                                                                             \
	if (is_digit(c)) {                                                                                                   \
		m_output = c - '0';                                                                                              \
	} else if (c >= 'a' && c <= 'f') {                                                                                   \
		m_output = c - 'a' + 10;                                                                                         \
	} else if (c >= 'A' && c <= 'F') {                                                                                   \
		m_output = c - 'A' + 10;                                                                                         \
	} else {                                                                                                             \
		ERR_FAIL_V_MSG(Vector<uint8_t>(), "Invalid hexadecimal character \"" + chr(c) + "\" at index " + m_index + "."); \
	}
	Vector<uint8_t> out;
	int len = length() / 2;
	out.resize(len);
	for (int i = 0; i < len; i++) {
		char32_t c;
		HEX_TO_BYTE(first, i * 2);
		HEX_TO_BYTE(second, i * 2 + 1);
		out.write[i] = first * 16 + second;
	}
	return out;
#undef HEX_TO_BYTE
}
void ::print_unicode_error(const  &p_message, bool p_critical) const {