doc: Fix up title case
This fixes some instances that were missed in earlier processings and
that now look a bit strange because they are inconsistent with nearby
titles.
Branch
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REL_12_STABLE
Details
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https://git.postgresql.org/pg/commitdiff/4534a1e81039866f1a0c4326e0458031a8ef483e
Modified Files
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doc/src/sgml/dml.sgml | 2 +-
doc/src/sgml/func.sgml | 2 +-
doc/src/sgml/plpgsql.sgml | 2 +-
3 files changed, 3 insertions(+), 3 deletions(-)