RFR: JDK-8309134: Augment test/langtools/tools/javac/versions/Versions.java for JDK 21 language changes [v3]

[Joe Darcy]

> Augment the Versions.java test in the usual way for new language changes.

Joe Darcy has updated the pull request incrementally with one additional commit since the last revision:

  Fix whitespace.

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Changes:
  - all: https://git.openjdk.org/jdk/pull/14229/files
  - new: https://git.openjdk.org/jdk/pull/14229/files/32879ef4..b2a947af

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=14229&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=14229&range=01-02

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/14229.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/14229/head:pull/14229

PR: https://git.openjdk.org/jdk/pull/14229