RFR: 7903181: port jextract for foreign-preview changes [v5]

[Athijegannathan Sundararajan]

> 7903181: port jextract for foreign-preview changes

Athijegannathan Sundararajan has updated the pull request incrementally with one additional commit since the last revision:

  changed 18 to 19 and JEP URL in README.md

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Changes:
  - all: https://git.openjdk.java.net/jextract/pull/35/files
  - new: https://git.openjdk.java.net/jextract/pull/35/files/49e374eb..8ab59509

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jextract&pr=35&range=04
 - incr: https://webrevs.openjdk.java.net/?repo=jextract&pr=35&range=03-04

  Stats: 4 lines in 1 file changed: 0 ins; 0 del; 4 mod
  Patch: https://git.openjdk.java.net/jextract/pull/35.diff
  Fetch: git fetch https://git.openjdk.java.net/jextract pull/35/head:pull/35

PR: https://git.openjdk.java.net/jextract/pull/35