[HUDI-1303] Some improvements for the HUDI Test Suite. (#2128)

1. Use the DAG Node's label from the yaml as its name instead of UUID names which are not descriptive when debugging issues from logs.
2. Fix CleanNode constructor which is not correctly implemented
3. When generating upsets, allows more granualar control over the number of inserts and upserts - zero or more inserts and upserts can be specified instead of always requiring both inserts and upserts.
4. Fixed generation of records of specific size
   - The current code was using a class variable "shouldAddMore" which was reset to false after the first record generation causing subsequent records to be of minimum size.
   - In this change, we pre-calculate the extra size of the complex fields. When generating records, for complex fields we read the field size from this map.
5. Refresh the timeline of the DeltaSync service before calling readFromSource. This ensures that only the newest generated data is read and data generated in the older Dag Nodes is ignored (as their AVRO files will have an older timestamp).
6. Making --workload-generator-classname an optional parameter as most probably the default will be used

docker/compose/hadoop.env

@@ -21,12 +21,13 @@ HIVE_SITE_CONF_javax_jdo_option_ConnectionUserName=hive
 HIVE_SITE_CONF_javax_jdo_option_ConnectionPassword=hive
 HIVE_SITE_CONF_datanucleus_autoCreateSchema=false
 HIVE_SITE_CONF_hive_metastore_uris=thrift://hivemetastore:9083
-HDFS_CONF_dfs_namenode_datanode_registration_ip___hostname___check=false
 
+HDFS_CONF_dfs_namenode_datanode_registration_ip___hostname___check=false
 HDFS_CONF_dfs_webhdfs_enabled=true
 HDFS_CONF_dfs_permissions_enabled=false
 #HDFS_CONF_dfs_client_use_datanode_hostname=true
 #HDFS_CONF_dfs_namenode_use_datanode_hostname=true
+HDFS_CONF_dfs_replication=1
 
 CORE_CONF_fs_defaultFS=hdfs://namenode:8020
 CORE_CONF_hadoop_http_staticuser_user=root