HDDS-12152. Stop testing with Hadoop 3.1.2 (#7773)

Author: adoroszlai

hadoop-ozone/dist/src/main/compose/common/hadoop-test.sh

@@ -25,9 +25,8 @@ export COMPOSE_FILE="${COMPOSE_FILE:-docker-compose.yaml}":../common/${extra_com
 : ${HADOOP_TEST_IMAGES:=""}
 
 if [[ -z "${HADOOP_TEST_IMAGES}" ]]; then
-  # hadoop2 and flokkr images are only available from Docker Hub
+  # hadoop2 image is only available from Docker Hub
   HADOOP_TEST_IMAGES="${HADOOP_TEST_IMAGES} apache/hadoop:${hadoop2.version}"
-  HADOOP_TEST_IMAGES="${HADOOP_TEST_IMAGES} flokkr/hadoop:3.1.2"
   HADOOP_TEST_IMAGES="${HADOOP_TEST_IMAGES} ${HADOOP_IMAGE}:${hadoop.version}"
 fi