hide log of jasync lib

src/main/resources/logback.xml

@@ -8,5 +8,6 @@
         <appender-ref ref="STDOUT"/>
     </root>
     <logger name="org.eclipse.jetty" level="INFO"/>
+    <logger name="com.github.jasync" level="WARN"/>
     <logger name="io.netty" level="INFO"/>
 </configuration>