RFR: Merge openjdk/jdk21u:master [v2]

[William Kemper]

> Merges tag jdk-21.0.9+6

William Kemper has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains 13 commits:

 - Merge branch 'master' into merge-jdk-21.0.9+6
 - 8360518: Docker tests do not work when asan is configured
   
   Reviewed-by: rschmelter
   Backport-of: 01b15bc1f961f43ae11db0c15f45763c4ec4180b
 - 8362855: Test java/net/ipv6tests/TcpTest.java should report SkippedException when there no ia4addr  or ia6addr
   
   Backport-of: 0f49f65af3ac85b93ccf140dcfad823fb03b5ce1
 - 8350807: Certificates using MD5 algorithm that are disabled by default are incorrectly allowed in TLSv1.3 when re-enabled
   
   Reviewed-by: mbaesken
   Backport-of: abb23828f9dc5f4cdb75d5b924dd6f45925102cd
 - 8342074: Fix runtime/Thread/TestAlwaysPreTouchStacks.java to be flagless or accept VM flags
   
   Reviewed-by: rschmelter
   Backport-of: 9291abc6337f8cf480806f4b2996ec905b021704
 - 8351487: [ubsan] jvmti.h runtime error: load of value which is not a valid value
   
   Backport-of: bf3cfbeff414356aaf2b0933568ff648beace2c5
 - 8352765: G1CollectedHeap::expand_and_allocate() may fail to allocate even after heap expansion succeeds
   
   Backport-of: 804a8fa4e96a32be2b38c2d0906dc5861a292007
 - 8338939: Simplify processing of hidden class names
   
   Backport-of: 0f667103db7842fe9d3399f56baee0a5def4529e
 - 8343607: C2: Shenandoah crashes during barrier expansion in Continuation::enter
   
   Reviewed-by: shade
   Backport-of: 45c914c3ad8fbc406af9ba9dec97f11c28c91299
 - 8355429: Open source ProgressMonitor test
   
   Backport-of: 3b7f43f95e061274020deaa1eecdb8182a6b64e1
 - ... and 3 more: https://git.openjdk.org/shenandoah-jdk21u/compare/d0d9b7e3...a0e383ad

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Changes: https://git.openjdk.org/shenandoah-jdk21u/pull/217/files
  Webrev: https://webrevs.openjdk.org/?repo=shenandoah-jdk21u&pr=217&range=01
  Stats: 1008 lines in 51 files changed: 712 ins; 205 del; 91 mod
  Patch: https://git.openjdk.org/shenandoah-jdk21u/pull/217.diff
  Fetch: git fetch https://git.openjdk.org/shenandoah-jdk21u.git pull/217/head:pull/217

PR: https://git.openjdk.org/shenandoah-jdk21u/pull/217