[Feature][KafkaSource]Add customize the row separator.

[lightzhao]

Purpose of this pull request

Add customize the row separator, if a message contains multiple row of data, you can customize the line separator to split. Config:

env {
  # You can set flink configuration here
  execution.parallelism = 1
  job.mode = "STREAMING"
  execution.planner = blink
  job.name = "kafka_hive_row_delimiter_test"
  execution.checkpoint.interval = 60000
}

source {
  Kafka {
    result_table_name = "kafka_table"
    schema = {
      fields {
        c1 = "string"
        c2 = "string"
        c3 = "string"
      }
    }
    format = text
    field_delimiter = ","
    topic = "test_topic_row_delimiter"
    bootstrap.servers = "kafkacluster:9092"
    kafka.max.poll.records = 500
    row_delimiter = "\\n"
 }
}

transform {
  sql {
    sql = "select c1,c2,c3,CAST(DATE_FORMAT(CAST(NOW() AS VARCHAR),'yyyyMMdd') as VARCHAR) as dt from kafka_table"
  }
}

sink {
  Console{}
  Hive {
    table_name = "db_test1.tmp_test03"
    metastore_uri = "thrift://hive:9083"
    partition_dir_expression = "${v0}"
  }
}

Test screenshot

Check list

• [ ] Code changed are covered with tests, or it does not need tests for reason:
• [ ] If any new Jar binary package adding in your PR, please add License Notice according New License Guide
• [ ] If necessary, please update the documentation to describe the new feature. https://github.com/apache/incubator-seatunnel/tree/dev/docs
• [ ] If you are contributing the connector code, please check that the following files are updated:
  1. Update change log that in connector document. For more details you can refer to connector-v2
  2. Update plugin-mapping.properties and add new connector information in it
  3. Update the pom file of seatunnel-dist
• [ ] Update the release-note.

[lightzhao]

please approve ci check.

[lightzhao]

@Hisoka-X @TyrantLucifer please approve ci check.

[lightzhao]

@Hisoka-X @TyrantLucifer @hailin0 PTAL.

[lightzhao]

@Hisoka-X @TyrantLucifer @hailin0 PTAL.

[lightzhao]

please approve ci , thanks.

[lightzhao]

please approve ci.

[lightzhao]

@Hisoka-X @EricJoy2048 @TyrantLucifer please approve ci.

[lightzhao]

@Hisoka-X @EricJoy2048 @TyrantLucifer please approve ci.

[Hisoka-X]

Sorry for late response. Let me check now!