pgsql: Doc: add missing punctuation - Mailing list pgsql-committers

Doc: add missing punctuation

Author: Daisuke Higuchi <higuchi.daisuke11@gmail.com>
Reviewed-by: Robert Treat <rob@xzilla.net>
Discussion: https://postgr.es/m/CAEVT6c-yWYstu76YZ7VOxmij2XA8vrOEvens08QLmKHTDjEPBw@mail.gmail.com
Backpatch-through: 14

Branch
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REL_18_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/789016be8ef015f65e9f76e5a58945b7b93f17b7

Modified Files
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doc/src/sgml/config.sgml  | 2 +-
doc/src/sgml/history.sgml | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)