security: upgrade Netty to 4.1.115.Final to fix CVE

- Upgrade netty.version from 4.1.100.Final to 4.1.115.Final
- Fixes GHSA-prj3-ccx8-p6x4: MadeYouReset HTTP/2 DDoS vulnerability
- Netty 4.1.115.Final includes patches for high severity DoS attack
- Addresses GitHub dependency review security alert

test/java/spark/pom.xml

@@ -22,7 +22,7 @@
         <junit.version>4.13.2</junit.version>
         <seaweedfs.hadoop3.client.version>3.80</seaweedfs.hadoop3.client.version>
         <jackson.version>2.15.3</jackson.version>
-        <netty.version>4.1.100.Final</netty.version>
+        <netty.version>4.1.115.Final</netty.version>
         <surefire.jvm.args>
             -Xmx2g
             -Dhadoop.home.dir=/tmp