doc: add markup for PG 12 release note text
I will add links to other parts of the docs later.
Branch
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master
Details
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https://git.postgresql.org/pg/commitdiff/c65bcfe9aeecae1c6204ad60612fae43669a88b0
Modified Files
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doc/src/sgml/release-12.sgml | 410 +++++++++++++++++++++----------------------
1 file changed, 205 insertions(+), 205 deletions(-)
