pgsql: doc PG relnotes: add links to commits

doc PG relnotes: add links to commits

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

Backpatch-through: 12

Branch
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REL_13_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/3ce928fe58889e1004c686187963daba35ecd441

Modified Files
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doc/src/sgml/release-13.sgml | 1167 ++++++++++++++++++++++++++++++++++++++++++
1 file changed, 1167 insertions(+)