align kafka versions

Author: yeikel

api/pom.xml

@@ -50,7 +50,10 @@
         <dependency>
             <groupId>org.apache.kafka</groupId>
             <artifactId>kafka-clients</artifactId>
-            <version>${kafka-clients.version}</version>
+            <!-- ccs stands for Confluent Community Edition
+             See https://www.confluent.io/confluent-community-license-faq/
+             -->
+            <version>${confluent.version}-ccs</version>
         </dependency>
         <dependency>
             <groupId>org.apache.commons</groupId>

e2e-tests/pom.xml

@@ -12,7 +12,6 @@
     <artifactId>e2e-tests</artifactId>
 
     <properties>
-        <kafka.version>3.8.0</kafka.version>
         <contract>${project.version}</contract>
         <maven.compiler.release>21</maven.compiler.release>
         <maven.surefire.release>3.5.1</maven.surefire.release>
@@ -25,7 +24,7 @@
         <dependency>
             <groupId>org.apache.kafka</groupId>
             <artifactId>kafka_2.13</artifactId>
-            <version>${kafka.version}</version>
+            <version>${confluent.version}-ccs</version>
         </dependency>
         <dependency>
             <groupId>io.kafbat.ui</groupId>

pom.xml

@@ -39,7 +39,6 @@
         <datasketches-java.version>3.1.0</datasketches-java.version>
         <groovy.version>3.0.13</groovy.version>
         <jackson.version>2.14.0</jackson.version>
-        <kafka-clients.version>3.8.0</kafka-clients.version>
         <org.mapstruct.version>1.6.2</org.mapstruct.version>
         <org.projectlombok.version>1.18.34</org.projectlombok.version>
         <protobuf-java.version>3.25.5</protobuf-java.version>