add CopyObject optimization when source and destination are same

[harshavardhana]

Description

add CopyObject optimization when source and destination are the same

Motivation and Context

when source and destination are the same and versioning is enabled
on the destination bucket - we do not need to re-create the entire
an object once again to optimize for space utilization.

Cases this PR is not supporting

• any pre-existing legacy object will not
  be preserved in this manner, meaning a new
  dataDir will be created.

• key-rotation and storage class changes
  of course will never re-use the dataDir

How to test this PR?

1. there is a fresh bucket with versioning enabled without any objects
2. upload an object passwd - version-1
3. delete passwd - deleteMarker version-2
4. do copy-object of version-1 to create a new version-3 but the contents are same as version-1
   - i.e now new dataDir is created

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• Fixes a regression (If yes, please add commit-id or PR # here)
• Documentation needed
• Unit tests needed

[minio-trusted]

Mint Automation

Test	Result
mint-xl.sh	✔️
mint-large-bucket.sh	✔️
mint-dist-xl.sh	✔️
mint-gateway-s3.sh	✔️
mint-gateway-azure.sh	✔️
mint-zoned.sh	✔️
mint-gateway-nas.sh	✔️
mint-fs.sh	❌ more...

10170-327635b/mint-fs.sh.log:

Running with
SERVER_ENDPOINT:      minio-dev6.minio.io:31955
ACCESS_KEY:           minio
SECRET_KEY:           ***REDACTED***
ENABLE_HTTPS:         0
SERVER_REGION:        us-east-1
MINT_DATA_DIR:        /mint/data
MINT_MODE:            full
ENABLE_VIRTUAL_STYLE: 0

To get logs, run 'docker cp 804084310b45:/mint/log /tmp/mint-logs'

(1/15) Running aws-sdk-go tests ... done in 0 seconds
(2/15) Running aws-sdk-java tests ... done in 1 seconds
(3/15) Running aws-sdk-php tests ... done in 41 seconds
(4/15) Running aws-sdk-ruby tests ... done in 2 seconds
(5/15) Running awscli tests ... done in 1 minutes and 3 seconds
(6/15) Running healthcheck tests ... done in 1 seconds
(7/15) Running mc tests ... done in 25 seconds
(8/15) Running minio-dotnet tests ... done in 27 seconds
(9/15) Running minio-go tests ... done in 24 seconds
(10/15) Running minio-java tests ... done in 21 seconds
(11/15) Running minio-js tests ... FAILED in 12 seconds
{
  "name": "minio-js",
  "function": "\"after all\" hook in \"functional tests\"",
  "duration": 6,
  "status": "FAIL",
  "error": "S3Error: The bucket you tried to delete is not empty at Object.parseError (node_modules/minio/dist/main/xml-parsers.js:86:11) at /mint/run/core/minio-js/node_modules/minio/dist/main/transformers.js:156:22 at DestroyableTransform._flush (node_modules/minio/dist/main/transformers.js:80:10) at DestroyableTransform.prefinish (node_modules/readable-stream/lib/_stream_transform.js:129:10) at prefinish (node_modules/readable-stream/lib/_stream_writable.js:611:14) at finishMaybe (node_modules/readable-stream/lib/_stream_writable.js:620:5) at endWritable (node_modules/readable-stream/lib/_stream_writable.js:643:3) at DestroyableTransform.Writable.end (node_modules/readable-stream/lib/_stream_writable.js:571:22) at IncomingMessage.onend (_stream_readable.js:673:10) at endReadableNT (_stream_readable.js:1201:12) at processTicksAndRejections (internal/process/task_queues.js:84:21)"
}
(11/15) Running minio-py tests ... done in 56 seconds
(12/15) Running s3cmd tests ... done in 14 seconds
(13/15) Running s3select tests ... done in 2 seconds
(14/15) Running security tests ... done in 0 seconds

Executed 14 out of 15 tests successfully.

Deleting image on docker hub
Deleting image locally

[harshavardhana]

ping @krishnasrinivas @poornas

[poornas]

LGTM