[Backport 2.x] Consume all params and content on extension Rest Request exception

[opensearch-trigger-bot]

Backport 1f6a3bc from #8096.

[github-actions]

Gradle Check (Jenkins) Run Completed with:

• RESULT: UNSTABLE ❕
• TEST FAILURES:

      2 org.opensearch.search.SearchWeightedRoutingIT.testStrictWeightedRoutingWithCustomString
      1 org.opensearch.remotestore.SegmentReplicationUsingRemoteStoreIT.testPressureServiceStats

• URL: https://build.ci.opensearch.org/job/gradle-check/18043/
• CommitID: 949f40e
  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

Merging #8183 (949f40e) into 2.x (1465a45) will increase coverage by 0.04%.
The diff coverage is 0.00%.

@@             Coverage Diff              @@
##                2.x    #8183      +/-   ##
============================================
+ Coverage     70.63%   70.67%   +0.04%     
  Complexity    56854    56854              
============================================
  Files          4703     4703              
  Lines        269102   269104       +2     
  Branches      39774    39774              
============================================
+ Hits         190069   190200     +131     
+ Misses        62771    62597     -174     
- Partials      16262    16307      +45     

Impacted Files	Coverage Δ
...rch/rest/extensions/RestSendToExtensionAction.java	46.66% <0.00%> (-0.80%)	⬇️

... and 452 files with indirect coverage changes