Bump remaining ZooKeeper test servers to 3.9 (curator 5.x needs server 3.6+)

Same root cause as the cluster e2e: the OAP's curator 5.9.0 client uses persistent
watches (addWatch, ZooKeeper 3.6.0+), which a zookeeper:3.5 server rejects
("unknown type 106") -> ConnectionLoss. This made the Integration test suite hang
(1h timeout, via the two zk testcontainer ITs) and the Virtual Gateway e2e fail
(oap1 unhealthy).

Bump the three remaining OAP-coordinator test servers zookeeper:3.5 -> 3.9:
- ClusterModuleZookeeperProviderFunctionalIT (cluster-zookeeper-plugin)
- ZookeeperConfigurationIT (configuration-zookeeper)
- e2e cases/gateway/docker-compose.yml

Validated locally on zk:3.9: both ITs pass (5 + 2 tests, no hang).

Author: wu-sheng

oap-server/server-cluster-plugin/cluster-zookeeper-plugin/src/test/java/org/apache/skywalking/oap/server/cluster/plugin/zookeeper/ClusterModuleZookeeperProviderFunctionalIT.java

@@ -60,7 +60,7 @@ public class ClusterModuleZookeeperProviderFunctionalIT {
 
     @Container
     public final GenericContainer<?> container =
-        new GenericContainer<>(DockerImageName.parse("zookeeper:3.5"))
+        new GenericContainer<>(DockerImageName.parse("zookeeper:3.9"))
             .waitingFor(Wait.forLogMessage(".*binding to port.*", 1))
             .withExposedPorts(2181);
 

oap-server/server-configuration/configuration-zookeeper/src/test/java/org/apache/skywalking/oap/server/configuration/zookeeper/it/ZookeeperConfigurationIT.java

@@ -57,7 +57,7 @@ public class ZookeeperConfigurationIT {
 
     @Container
     public final GenericContainer<?> container =
-        new GenericContainer<>(DockerImageName.parse("zookeeper:3.5"))
+        new GenericContainer<>(DockerImageName.parse("zookeeper:3.9"))
             .waitingFor(Wait.forLogMessage(".*binding to port.*", 1))
             .withExposedPorts(2181);
 

test/e2e-v2/cases/gateway/docker-compose.yml

@@ -15,7 +15,7 @@
 
 services:
   zk:
-    image: zookeeper:3.5
+    image: zookeeper:3.9
     expose:
       - 2181
     networks: