[jdk21u-dev] RFR: 8320145: Compiler should accept final variable in Record Pattern

[Aleksey Shipilev]

Clean backport to fix the new language feature in JDK 21. The patch extends the space of compilable programs.

Additional testing:
 - [x] New regression test fails without the fix, passes with it
 - [x] macos-aarch64-server-fastdebug, `langtools_all`

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Commit messages:
 - Backport 4ba94ef69ef2ee576c50bb6003a795746dcdf30d

Changes: https://git.openjdk.org/jdk21u-dev/pull/125/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=125&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8320145
  Stats: 48 lines in 3 files changed: 44 ins; 2 del; 2 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/125.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/125/head:pull/125

PR: https://git.openjdk.org/jdk21u-dev/pull/125