Upgrade Apache Kafka Client to 2.5.0 (#584)

(cherry picked from commit 351f53e)

pom.xml

@@ -81,6 +81,7 @@
         <ldaptive.version>1.2.3</ldaptive.version>
         <http.commons.version>4.5.3</http.commons.version>
         <cxf.version>3.2.14</cxf.version>
+        <kafka.version>2.5.0</kafka.version>
 
         <!-- assembly descriptors -->
         <elasticsearch.assembly.descriptor>${basedir}/src/main/assemblies/plugin.xml</elasticsearch.assembly.descriptor>
@@ -295,7 +296,7 @@
         <dependency>
             <groupId>org.apache.kafka</groupId>
             <artifactId>kafka-clients</artifactId>
-            <version>2.0.1</version>
+            <version>${kafka.version}</version>
             <exclusions>
                 <exclusion>
                     <artifactId>slf4j-api</artifactId>
@@ -458,7 +459,7 @@
         <dependency>
             <groupId>org.springframework.kafka</groupId>
             <artifactId>spring-kafka-test</artifactId>
-            <version>2.2.7.RELEASE</version>
+            <version>2.5.4.RELEASE</version>
             <scope>test</scope>
         </dependency>