the RethrottleTests assumed that tasks that were
unprepared to rethrottle would bubble up into the
Rethrottle response as an ElasticsearchException
wrapping an IllegalArgumentException. This seems to
have changed to potentially involve further levels of
wrapping.

This change makes the retry logic more resilient to
arbitrary nesting of the underlying IllegalArgumentException

the RethrottleTests assumed that tasks that were
unprepared to rethrottle would bubble up into the
Rethrottle response as an ElasticsearchException
wrapping an IllegalArgumentException. This seems to
have changed to potentially involve further levels of
wrapping.

This change makes the retry logic more resilient to
arbitrary nesting of the underlying IllegalArgumentException

the RethrottleTests assumed that tasks that were
unprepared to rethrottle would bubble up into the
Rethrottle response as an ElasticsearchException
wrapping an IllegalArgumentException. This seems to
have changed to potentially involve further levels of
wrapping.

This change makes the retry logic more resilient to
arbitrary nesting of the underlying IllegalArgumentException

the RethrottleTests assumed that tasks that were
unprepared to rethrottle would bubble up into the
Rethrottle response as an ElasticsearchException
wrapping an IllegalArgumentException. This seems to
have changed to potentially involve further levels of
wrapping.

This change makes the retry logic more resilient to
arbitrary nesting of the underlying IllegalArgumentException

…follow

* elastic/master: (37 commits)
  Enable test logging for TransformIntegrationTests#testSearchTransform.
  stronger wording for ilm+rollover in docs (elastic#39159)
  Mute SingleNodeTests (elastic#39156)
  AwaitsFix XPackUsageIT#testXPackCcrUsage.
  Resolve concurrency with watcher trigger service (elastic#39092)
  Fix median calculation in MedianAbsoluteDeviationAggregatorTests (elastic#38979)
  [DOCS] Edits the remote clusters documentation (elastic#38996)
  add version 6.6.2
  Revert "Mute failing test 20_mix_typless_typefull (elastic#38781)" (elastic#38912)
  Rebuild remote connections on profile changes (elastic#37678)
  Document 'max_size' parameter as shard size for rollover (elastic#38750)
  Add some missing toString() implementations (elastic#39124)
  Migrate Streamable to Writeable for cluster block package (elastic#37391)
  fix RethrottleTests retry (elastic#38978)
  Disable date parsing test in non english locale (elastic#39052)
  Remove BCryptTests (elastic#39098)
  [ML] Stop the ML memory tracker before closing node (elastic#39111)
  Allow retention lease operations under blocks (elastic#39089)
  ML refactor DatafeedsConfig(Update) so defaults are not populated in queries or aggs (elastic#38822)
  Fix retention leases sync on recovery test
  ...