pgsql: Fix grammar in error message - Mailing list pgsql-committers

Fix grammar in error message

While at it, make ellipses formatting consistent when describing SQL statements.

Ekaterina Kiryanova and Alexander Lakhin

Reviewed by myself and Álvaro Herrera
Discussion: https://www.postgresql.org/message-id/eed5cec0-a542-53da-6a5e-7789c6ed9817%40postgrespro.ru
Backpatch only the grammar fix to v15

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/7beda87b6a4e5eae66f06df313581f7f53cab813

Modified Files
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src/backend/commands/subscriptioncmds.c | 4 ++--
src/backend/postmaster/bgworker.c       | 2 +-
src/backend/rewrite/rewriteHandler.c    | 2 +-
src/test/regress/expected/with.out      | 4 ++--
src/test/regress/sql/with.sql           | 2 +-
5 files changed, 7 insertions(+), 7 deletions(-)