* master:
  [ML] Rate limit established model memory updates (#31768)
  [Docs] Correct default window_size (#31582)
  S3 fixture should report 404 on unknown bucket (#31782)
  Detach Transport from TransportService (#31727)
  [ML] Limit ML filter items to 10K (#31731)
  [ML] Return statistics about forecasts as part of the jobsstats and usage API (#31647)
  Fixture for Minio testing (#31688)
  [DOCS] Add missing get mappings docs to HLRC (#31765)
  [DOCS] Starting Elasticsearch (#31701)
  Painless: Complete Removal of Painless Type (#31699)
  Fix not waiting for Netty ThreadDeathWatcher in IT (#31758)
  Consolidate watcher setting update registration (#31762)
  Build: re-enabled bwc (#31769)
  ingest: Introduction of a bytes processor (#31733)
  Fix coerce validation_method in GeoBoundingBoxQueryBuilder (#31747)
  Add analyze API to high-level rest client (#31577)
  [DOCS] Typos
  DOC: Add examples to the SQL docs (#31633)
  Add support for AWS session tokens (#30414)
  Watcher: Reenable start/stop yaml tests (#31754)
  Implemented XContent serialisation for GetIndexResponse (#31675)
  JDBC: Fix stackoverflow on getObject and timestamp conversion (#31735)
  resolveHasher defaults to NOOP (#31723)
  Account for XContent overhead in in-flight breaker
  Split CircuitBreaker-related tests (#31659)
  Add write*Blob option to replace existing blob (#31729)
  Painless: Add Context Docs (#31190)
  Watcher: Fix chain input toXcontent serialization (#31721)
  Docs: Match the examples in the description (#31710)
  rest-high-level: added get cluster settings (#31706)
  [Docs] Correct typos (#31720)
  Clean up double semicolon code typos (#31687)
  [DOCS] Check for Windows and *nix file paths (#31648)
  [ML] Validate ML filter_id (#31535)
  Revert long lines
  Fix TransportChangePasswordActionTests

Today TransportService is tightly coupled with Transport since it
requires an instance of TransportService in order to receive responses
and send requests. This is mainly due to the Request and Response handlers
being maintained in TransportService but also because of the lack of a proper
callback interface.

This change moves request handler registry and response handler registration into
Transport and adds all necessary methods to `TransportConnectionListener` in order
to remove the `TransportService` dependency from `Transport`
Transport now accepts one or more `TransportConnectionListener` instances that are
executed sequentially in a blocking fashion.

Today TransportService is tightly coupled with Transport since it
requires an instance of TransportService in order to receive responses
and send requests. This is mainly due to the Request and Response handlers
being maintained in TransportService but also because of the lack of a proper
callback interface.

This change moves request handler registry and response handler registration into
Transport and adds all necessary methods to `TransportConnectionListener` in order
to remove the `TransportService` dependency from `Transport`
Transport now accepts one or more `TransportConnectionListener` instances that are
executed sequentially in a blocking fashion.

* 6.x:
  Test: Do not remove xpack templates when cleaning (#31642)
  SQL: Allow long literals (#31777)
  SQL: Fix incorrect message for aliases (#31792)
  Detach Transport from TransportService (#31727)
  6.3.1 release notes (#31829)
  Add unreleased version 6.3.2
  [ML][TEST] Use java 11 valid time format in DataDescriptionTests (#31817)
  [ML] Don't treat stale FAILED jobs as OPENING in job allocation (#31800)
  [ML] Fix calendar and filter updates from non-master nodes (#31804)
  Fix license header generation on Windows (#31790)
  mark XPackRestIT.test {p0=monitoring/bulk/10_basic/Bulk indexing of monitoring data} as AwaitsFix
  Add JDK11 support without enabling in CI (#31644)
  Watcher: Fix check for currently executed watches (#31137)
  [DOCS] Fixes 6.3.0 release notes (#31771)
  Watcher: Ensure correct method is used to read secure settings (#31753)
  [ML] Rate limit established model memory updates (#31768)
  SQL: Update CLI logo