private void initAttachment() {
        InterceptorScopeInvocation invocation = interceptorScope.getCurrentInvocation();
        if (invocation != null) {
            invocation.getOrCreateAttachment(HttpClient3CallContextFactory.HTTPCLIENT3_CONTEXT_FACTORY);
        }
    }
@author Minwoo Jung
@author jaehong.kim
agent-module/plugins/httpclient3/src/main/java/com/navercorp/pinpoint/plugin/httpclient3/interceptor/HttpMethodBaseExecuteMethodInterceptor.java