RFR: 8308307: Update to gcc 12.2.0 on Linux

[Kevin Rushforth]

Update the compiler on Linux to gcc 12.2. This provides the needed C++20 support for the next WebKit update.

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Commit messages:
 - 8308307: Update to gcc 12.2.0 on Linux

Changes: https://git.openjdk.org/jfx/pull/1141/files
 Webrev: https://webrevs.openjdk.org/?repo=jfx&pr=1141&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8308307
  Stats: 7 lines in 3 files changed: 0 ins; 0 del; 7 mod
  Patch: https://git.openjdk.org/jfx/pull/1141.diff
  Fetch: git fetch https://git.openjdk.org/jfx.git pull/1141/head:pull/1141

PR: https://git.openjdk.org/jfx/pull/1141