RFR: 7903735: Remove redundant method in generated code

[Nizar Benalla]

Was looking at older issues and saw an opportunity for a refractor.
I don't see a dependent PR feature for this repo but this is meant to be merged after https://github.com/openjdk/jextract/pull/265

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Commit messages:
 - use newer method from JDK 23

Changes: https://git.openjdk.org/jextract/pull/266/files
  Webrev: https://webrevs.openjdk.org/?repo=jextract&pr=266&range=00
  Issue: https://bugs.openjdk.org/browse/CODETOOLS-7903735
  Stats: 2 lines in 1 file changed: 0 ins; 1 del; 1 mod
  Patch: https://git.openjdk.org/jextract/pull/266.diff
  Fetch: git fetch https://git.openjdk.org/jextract.git pull/266/head:pull/266

PR: https://git.openjdk.org/jextract/pull/266