pgsql: scripts: add Perl script to add links to release notes

scripts: add Perl script to add links to release notes

Reported-by: jian he

Discussion: /messages/by-id/ZuYsS5XdA7hVcV9l@momjian.us

Backpatch-through: 12

Branch
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REL_15_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/ccd1ddc50750129a7900948ac28eef907bdbed51

Modified Files
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src/tools/RELEASE_CHANGES | 1 +
src/tools/add_commit_links.pl | 136 ++++++++++++++++++++++++++++++++++++++++++
2 files changed, 137 insertions(+)