HDDS-14049. [DiskBalancer] Missing stop-after-disk-even in DiskBalancer status output and doc updation

[Gargi-jais11]

What changes were proposed in this pull request?

The DiskBalancer status output is incomplete, as it does not show the stop-after-disk-even configuration.

**Design and Feature Doc Update **
Update DiskBalancer.md design doc to have description example to enable authentication to the required user to start, stop or update diskbalancer command. By default only dn can start, stop and update.

What is the link to the Apache JIRA

https://issues.apache.org/jira/browse/HDDS-14049

How was this patch tested?

Tested manually.

bash-5.1$ ozone admin datanode diskbalancer status --in-service-datanodes
Status result:
Datanode                            Status          Threshold(%)    BandwidthInMB   Threads      StopAfterDiskEven    SuccessMove  FailureMove  BytesMoved(MB)  EstBytesToMove(MB) EstTimeLeft(min)    
ozone-datanode-3.ozone_default      STOPPED         10.0000         10              5            true                 0            0            0               0               0                   
ozone-datanode-4.ozone_default      STOPPED         10.0000         10              5            true                 0            0            0               0               0                   
ozone-datanode-2.ozone_default      STOPPED         10.0000         10              5            true                 0            0            0               0               0                   
ozone-datanode-5.ozone_default      STOPPED         10.0000         10              5            true                 0            0            0               0               0                   
ozone-datanode-1.ozone_default      STOPPED         10.0000         10              5            true                 0            0            0               0               0                   

Note: Estimated time left is calculated based on the estimated bytes to move and the configured disk bandwidth.
bash-5.1$ ozone admin datanode diskbalancer status ozone-datanode-1 --json
[ {
  "datanode" : "ozone-datanode-1.ozone_default",
  "action" : "status",
  "status" : "success",
  "serviceStatus" : "STOPPED",
  "threshold" : 10.0,
  "bandwidthInMB" : 10,
  "threads" : 5,
  "stopAfterDiskEven" : true,
  "successMove" : 0,
  "failureMove" : 0,
  "bytesMovedMB" : 0,
  "estBytesToMoveMB" : 0,
  "estTimeLeftMin" : 0
} ]

bash-5.1$ ozone admin datanode diskbalancer update -s false ozone-datanode-1      
Updated DiskBalancer configuration on nodes: [ozone-datanode-1]

bash-5.1$ ozone admin datanode diskbalancer status --in-service-datanodes
Status result:
Datanode                            Status          Threshold(%)    BandwidthInMB   Threads      StopAfterDiskEven    SuccessMove  FailureMove  BytesMoved(MB)  EstBytesToMove(MB) EstTimeLeft(min)    
ozone-datanode-3.ozone_default      STOPPED         10.0000         10              5            true                 0            0            0               0               0                   
ozone-datanode-4.ozone_default      STOPPED         10.0000         10              5            true                 0            0            0               0               0                   
ozone-datanode-2.ozone_default      STOPPED         10.0000         10              5            true                 0            0            0               0               0                   
ozone-datanode-5.ozone_default      STOPPED         10.0000         10              5            true                 0            0            0               0               0                   
ozone-datanode-1.ozone_default      STOPPED         10.0000         10              5            false                0            0            0               0               0                   

Note: Estimated time left is calculated based on the estimated bytes to move and the configured disk bandwidth.

[ChenSammi]

@Gargi-jais11 , the overall change looks good to me. But it looks like there are duplicate contents in two diskbalancer.md, could you simplify the two diskbalancer.md, so each doc can have a focus? doc under design is about the design, and doc under feature is usually how to configure and use this feature.
Both code duplication and doc duplication are the avoid targets.

[Gargi-jais11]

@ChenSammi I have update both design and feature doc to be more focused on their respective part. Please have a look on it.

[ChenSammi]

Thanks @Gargi-jais11 .