RFR: Merge openjdk/jdk21u:master

[William Kemper]

Merges tag jdk-21.0.7-ga

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Commit messages:
 - 8353904: [21u] Remove designator DEFAULT_PROMOTED_VERSION_PRE=ea for release 21.0.7
 - 8331735: UpcallLinker::on_exit races with GC when copying frame anchor
 - 8339810: Clean up the code in sun.tools.jar.Main to properly close resources and use ZipFile during extract
 - 8309841: Jarsigner should print a warning if an entry is removed
 - 8347847: Enhance jar file support
 - 8343007: Enhance Buffered Image handling
 - 8342562: Enhance Deflater operations
 - 8338430: Improve compiler transformations
 - 8337692: Better TLS connection support
 - 8337494: Clarify JarInputStream behavior

The merge commit only contains trivial merges, so no merge-specific webrevs have been generated.

Changes: https://git.openjdk.org/shenandoah-jdk21u/pull/180/files
  Stats: 743 lines in 19 files changed: 504 ins; 87 del; 152 mod
  Patch: https://git.openjdk.org/shenandoah-jdk21u/pull/180.diff
  Fetch: git fetch https://git.openjdk.org/shenandoah-jdk21u.git pull/180/head:pull/180

PR: https://git.openjdk.org/shenandoah-jdk21u/pull/180