RFR: fixed samples for API change MemorySegment.slice -> asSlice and to re-extract libjimage binding

[Athijegannathan Sundararajan]

fixed samples for API change MemorySegment.slice -> asSlice and to re-extract libjimage binding

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Commit messages:
 - fixed samples for API change MemorySegment.slice -> asSlice and to re-extract libjimage binding

Changes: https://git.openjdk.org/jextract/pull/108/files
 Webrev: https://webrevs.openjdk.org/?repo=jextract&pr=108&range=00
  Stats: 3 lines in 2 files changed: 0 ins; 1 del; 2 mod
  Patch: https://git.openjdk.org/jextract/pull/108.diff
  Fetch: git fetch https://git.openjdk.org/jextract pull/108/head:pull/108

PR: https://git.openjdk.org/jextract/pull/108