public static String getBuiltinFormat(Short index, String defaultFormat, Locale locale) {
        if (index == null || index <= 0) {
            return defaultFormat;
        }

        // Give priority to checking if it is the default value for all languages
        if (index < BUILTIN_FORMATS_ALL_LANGUAGES.length) {
            String format = BUILTIN_FORMATS_ALL_LANGUAGES[index];
            if (format != null) {
                return format;
            }
        }

        // In other cases, give priority to using the externally provided format
        if (!StringUtils.isEmpty(defaultFormat) && !defaultFormat.startsWith(RESERVED)) {
            return defaultFormat;
        }

        // Finally, try using the built-in format
        String[] builtinFormat = switchBuiltinFormats(locale);
        if (index >= builtinFormat.length) {
            return defaultFormat;
        }
        return builtinFormat[index];
    }
Excel's built-in format conversion.Currently only supports Chinese.

<p>
If it is not Chinese, it is recommended to directly modify the builtinFormats, which will better support
internationalization in the future.

<p>
Specific correspondence please see:
https://docs.microsoft.com/en-us/dotnet/api/documentformat.openxml.spreadsheet.numberingformat?view=openxml-2.8.1

@author Jiaju Zhuang
fastexcel-core/src/main/java/cn/idev/excel/constant/BuiltinFormats.java