private String getSpanAttachedEventTagValue(List<KeyStringValuePair> values, String tagKey) {
        for (KeyStringValuePair pair : values) {
            if (Objects.equals(pair.getKey(), tagKey)) {
                return pair.getValue();
            }
        }
        return null;
    }
Reference from zipkin2.server.internal.ZipkinQueryApiV2 for the API consistent.
oap-server/server-query-plugin/zipkin-query-plugin/src/main/java/org/apache/skywalking/oap/query/zipkin/handler/ZipkinQueryHandler.java