### 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.
if (p_n == 1) {
		return text.replace("$DOCS_URL", VERSION_DOCS_URL);
	}
	return text_plural.replace("$DOCS_URL", VERSION_DOCS_URL);
}
#endif
/**
 * "Run-time TRanslate". Performs string replacement for internationalization
 * within a running project. The translation string must be supplied by the
 * project, as Godot does not provide built-in translations for `RTR()` strings
 * to keep binary size low. A translation context can optionally be specified to
 * disambiguate between identical source strings in translations. When
 * placeholders are desired, use `vformat(RTR("Example: %s"), some_string)`.
 * If a string mentions a quantity (and may therefore need a dynamic plural form),
 * use `RTRN()` instead of `RTR()`.
 *
 * NOTE: Do not use `RTR()` in editor-only code (typically within the `editor/`
 * folder). For editor translations, use `TTR()` instead.
 */
 RTR(const  &p_text, const  &p_context) {
	if (TranslationServer::get_singleton()) {
		 rtr = TranslationServer::get_singleton()->tool_translate(p_text, p_context);
		if (rtr.is_empty() || rtr == p_text) {
			return TranslationServer::get_singleton()->translate(p_text, p_context);
		} else {
			return rtr;
		}
	}
	return p_text;
}