[master] RFR: Merge jdk:jdk-21+4

[Roman Kennke]

Let's merge latest jdk21 tag.

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Commit messages:
 - Merge tag 'jdk-21+4' into merge-jdk21+4
 - 8299439: java/text/Format/NumberFormat/CurrencyFormat.java fails for hr_HR
 - 8299563: Fix typos
 - 8219810: javac throws NullPointerException
 - 8200610: Compiling fails with java.nio.file.ReadOnlyFileSystemException
 - Merge
 - 8299476: PPC64 Zero build fails after JDK-8286302
 - 8293824: gc/whitebox/TestConcMarkCycleWB.java failed "RuntimeException: assertTrue: expected true, was false"
 - 8299483: ProblemList java/text/Format/NumberFormat/CurrencyFormat.java
 - 8298324: Unable to run shell test with make
 - ... and 1276 more: https://git.openjdk.org/lilliput/compare/16e2a110...515ffce7

The webrevs contain the adjustments done while merging with regards to each parent branch:
 - master: https://webrevs.openjdk.org/?repo=lilliput&pr=61&range=00.0
 - jdk:jdk-21+4: https://webrevs.openjdk.org/?repo=lilliput&pr=61&range=00.1

Changes: https://git.openjdk.org/lilliput/pull/61/files
  Stats: 415414 lines in 5864 files changed: 211059 ins; 138427 del; 65928 mod
  Patch: https://git.openjdk.org/lilliput/pull/61.diff
  Fetch: git fetch https://git.openjdk.org/lilliput pull/61/head:pull/61

PR: https://git.openjdk.org/lilliput/pull/61