pgsql: Fix typos and grammar in graph table rewrite code

Fix typos and grammar in graph table rewrite code

Reported-by: Lakshmi N <lakshmin.jhs@gmail.com>
Author: Lakshmi N <lakshmin.jhs@gmail.com>
Author: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Discussion: https://www.postgresql.org/message-id/CA+3i_M9gpUGjH-BkJk=UFjK16jq9fEQHpmZ1cxpJO+xM4hWC+A@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/9082680c34e987d51f84c217e1dbd140d4a4517b

Modified Files
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src/backend/commands/propgraphcmds.c    | 12 ++++++------
src/backend/rewrite/rewriteGraphTable.c | 14 +++++++-------
2 files changed, 13 insertions(+), 13 deletions(-)