[Backport] [2.x] Added featureflag (#8988)

[reta]

Backport of #8988 to 2.x

[github-actions]

Gradle Check (Jenkins) Run Completed with:

• RESULT: SUCCESS ✅
• URL: https://build.ci.opensearch.org/job/gradle-check/21703/
• CommitID: c8d6474

[codecov]

Codecov Report

Merging #9066 (c8d6474) into 2.x (618dba4) will increase coverage by 0.02%.
Report is 1 commits behind head on 2.x.
The diff coverage is n/a.

@@             Coverage Diff              @@
##                2.x    #9066      +/-   ##
============================================
+ Coverage     70.85%   70.87%   +0.02%     
- Complexity    57439    57455      +16     
============================================
  Files          4749     4749              
  Lines        271395   271395              
  Branches      40055    40055              
============================================
+ Hits         192287   192356      +69     
+ Misses        62623    62559      -64     
+ Partials      16485    16480       -5     

Files Changed	Coverage Δ
...g/opensearch/common/recycler/AbstractRecycler.java	100.00% <ø> (ø)
.../opensearch/common/recycler/AbstractRecyclerC.java	100.00% <ø> (ø)
...earch/common/recycler/ConcurrentDequeRecycler.java	100.00% <ø> (ø)
.../org/opensearch/common/recycler/DequeRecycler.java	100.00% <ø> (ø)
...org/opensearch/common/recycler/FilterRecycler.java	100.00% <ø> (ø)
...a/org/opensearch/common/recycler/NoneRecycler.java	100.00% <ø> (ø)
...java/org/opensearch/common/recycler/Recyclers.java	91.42% <ø> (ø)
.../common/util/concurrent/ConcurrentCollections.java	90.90% <ø> (ø)
.../common/util/concurrent/ConcurrentHashMapLong.java	40.74% <ø> (ø)

... and 469 files with indirect coverage changes