build: upgrade testcontainers 1.16.3 to 1.21.4 to fix Docker Engine 29.x incompatibility

Testcontainers 1.16.3 uses the deprecated Docker API endpoint
GET /containers/{id}/json which was removed in Docker Engine 29.x,
causing container launch failures. Upgrading to 1.21.4 resolves this.

Author: yeikel

pom.xml

@@ -41,7 +41,7 @@
         <lz4.version>1.10.1</lz4.version>
         <hamcrest.version>1.3</hamcrest.version>
         <gson.version>2.9.0</gson.version>
-        <test.containers.version>1.16.3</test.containers.version>
+        <test.containers.version>1.21.4</test.containers.version>
         <kafka.connect.maven.plugin.version>0.11.1</kafka.connect.maven.plugin.version>
         <maven.release.plugin.version>2.5.3</maven.release.plugin.version>
         <hadoop.version>3.3.1</hadoop.version>

src/test/java/io/confluent/connect/elasticsearch/helper/ElasticSearchMockUtil.java

@@ -29,7 +29,9 @@ static public ObjectNode addStandardVersionInfo(ObjectNode response) {
         .put("cluster_uuid", "83EJmDNrRVirBWcZDgs9ew")
         .put("tagline", "You Know, for Search")
         .putObject("version")
-        .put("number", "7.16.3")
+        .put("number", "8.19.15")
+        .put("build_flavor", "default")
+        .put("build_type", "tar")
         .put("build_hash", "83EJmDNrRVirBWcZDgs9ew")
         .put("build_date", "2018-04-12T16:25:14.838Z")
         .put("build_snapshot", "false")

src/test/java/io/confluent/connect/elasticsearch/helper/ElasticsearchContainer.java

@@ -72,7 +72,7 @@ public class ElasticsearchContainer
   /**
    * Default Elasticsearch version.
    */
-  public static final String DEFAULT_ES_VERSION = "8.15.2";
+  public static final String DEFAULT_ES_VERSION = "8.19.15";
 
   /**
    * Default Elasticsearch port.