### 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.
}
		}
	} else {
		for (int i = p_from; i <= (len - src_len); i++) {
			bool found = true;
			for (int j = 0; j < src_len; j++) {
				int read_pos = i + j;
				if (read_pos >= len) {
					ERR_PRINT("read_pos>=len");
					return -1;
				}
				if (src[read_pos] != (char32_t)p_str[j]) {
					found = false;
					break;
				}
			}
			if (found) {
				return i;
			}
		}
	}
	return -1;
}
int ::find_char(const char32_t &p_char, int p_from) const {
	return _cowdata.find(p_char, p_from);
}
int ::findmk(const Vector<> &p_keys, int p_from, int *r_key) const {
	if (p_from < 0) {
		return -1;
	}