private Map<String, String> parseAttr(Splitter splitter, String attr, String entrySplitterStr) {
            Map<String, String> map = new HashMap<>();
            for (String s : splitter.split(attr)) {
                int idx = s.indexOf(entrySplitterStr);
                String k = s;
                String v = null;
                if (idx > 0) {
                    k = s.substring(0, idx);
                    v = s.substring(idx + 1);
                }
                map.put(k, v);
            }
            return map;
        }
parseAttr from k1=v1&k2=v2 to kv map

@param splitter {@link Splitter}
@param attr String
@param entrySplitterStr String
@return {@link Map}
inlong-sdk/sort-sdk/src/main/java/org/apache/inlong/sdk/sort/fetcher/tube/TubeSingleTopicFetcher.java