[Backport 2.x] Changes to build star tree in off heap

[opensearch-trigger-bot]

Backport a918530 from #14817.

[github-actions]

❕ Gradle check result for 77e886a: UNSTABLE

Please review all flaky tests that succeeded after retry and create an issue if one does not already exist to track the flaky failure.

[codecov]

Codecov Report

Attention: Patch coverage is 82.51599% with 82 lines in your changes missing coverage. Please review.

Project coverage is 71.59%. Comparing base (4f97fd3) to head (77e886a).
Report is 4 commits behind head on 2.x.

Files	Patch %	Lines
...acube/startree/builder/OffHeapStarTreeBuilder.java	78.41%	27 Missing and 3 partials ⚠️
...startree/builder/AbstractDocumentsFileManager.java	74.69%	16 Missing and 5 partials ⚠️
...cube/startree/builder/StarTreeDocsFileManager.java	89.25%	5 Missing and 8 partials ⚠️
.../opensearch/common/util/ByteArrayBackedBitset.java	75.00%	7 Missing ⚠️
...tacube/startree/utils/StarTreeDocumentsSorter.java	86.36%	2 Missing and 1 partial ⚠️
...acube/startree/builder/SegmentDocsFileManager.java	93.75%	2 Missing ⚠️
...ex/datacube/startree/builder/StarTreesBuilder.java	50.00%	2 Missing ⚠️
...ex/codec/composite/Composite99DocValuesWriter.java	50.00%	0 Missing and 1 partial ⚠️
...datacube/startree/builder/BaseStarTreeBuilder.java	95.23%	0 Missing and 1 partial ⚠️
...ube/startree/utils/StarTreeDocumentBitSetUtil.java	91.66%	1 Missing ⚠️
... and 1 more

Additional details and impacted files

@@             Coverage Diff              @@
##                2.x   #15398      +/-   ##
============================================
+ Coverage     71.52%   71.59%   +0.07%     
- Complexity    63228    63398     +170     
============================================
  Files          5197     5204       +7     
  Lines        296727   297289     +562     
  Branches      43179    43269      +90     
============================================
+ Hits         212221   212850     +629     
+ Misses        66696    66584     -112     
- Partials      17810    17855      +45     

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