public static String toUtf8String(InputStream is) {
        return new String(toByteArray(is), StandardCharsets.UTF_8);
    }
Reads and returns the rest of the given input stream as a string.
Caller is responsible for closing the given input stream.

@param is The input stream to convert.
@return The converted string.
smithy-utils/src/main/java/software/amazon/smithy/utils/IoUtils.java