Bump org.apache.zookeeper:zookeeper from 3.9.3 to 3.9.4 in /scala/dllib

Bumps org.apache.zookeeper:zookeeper from 3.9.3 to 3.9.4.

---
updated-dependencies:
- dependency-name: org.apache.zookeeper:zookeeper
  dependency-version: 3.9.4
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

scala/dllib/pom.xml

@@ -134,7 +134,7 @@
         <dependency>
             <groupId>org.apache.zookeeper</groupId>
             <artifactId>zookeeper</artifactId>
-            <version>3.9.3</version>
+            <version>3.9.4</version>
             <scope>${spark-scope}</scope>
             <exclusions>
                 <exclusion>