public Map<String, String> getProperties() {
        return this.props;
    }
Get the original attribute map

Notice: only the non-pre-read fields need to be searched from the attribute map,
        the pre-read fields MUST be got according to the methods in the class.
inlong-dataproxy/dataproxy-source/src/main/java/org/apache/inlong/dataproxy/config/CommonConfigHolder.java