pgsql: Fix some typos and make small stylistic improvements

Fix some typos and make small stylistic improvements

for commit 2f094e7ac69

Author: zengman <zengman@halodbtech.com>
Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Discussion: /messages/by-id/a855795d-e697-4fa5-8698-d20122126567@eisentraut.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/5282bf535e474dc2517f2e835d147420ae2144de

Modified Files
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src/backend/rewrite/rewriteGraphTable.c | 32 +++++++++++++++-----------------
1 file changed, 15 insertions(+), 17 deletions(-)