RFR: 7903357: add a jextract sample that uses pcre2 library [v2]

[Athijegannathan Sundararajan]

> Simple sample that checks a given string for matches against the given regex

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

  review comments

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Changes:
  - all: https://git.openjdk.org/jextract/pull/88/files
  - new: https://git.openjdk.org/jextract/pull/88/files/d41707c6..06b1185e

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jextract&pr=88&range=01
 - incr: https://webrevs.openjdk.org/?repo=jextract&pr=88&range=00-01

  Stats: 39 lines in 4 files changed: 2 ins; 35 del; 2 mod
  Patch: https://git.openjdk.org/jextract/pull/88.diff
  Fetch: git fetch https://git.openjdk.org/jextract pull/88/head:pull/88

PR: https://git.openjdk.org/jextract/pull/88