pgsql: Fix misc typos in comments.

Fix misc typos in comments.

Spotted mostly by Fabien Coelho.

Discussion: https://www.postgresql.org/message-id/alpine.DEB.2.21.1901230947050.16643@lancre

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/95931133a959404cf7320b49058b2f1c2e4606b9

Modified Files
--------------
contrib/pgcrypto/pgp-decrypt.c        | 2 +-
contrib/postgres_fdw/postgres_fdw.c   | 2 +-
src/backend/access/gin/ginget.c       | 2 +-
src/backend/executor/execExprInterp.c | 2 +-
src/backend/executor/execParallel.c   | 2 +-
src/backend/executor/execTuples.c     | 2 +-
src/backend/parser/gram.y             | 2 +-
src/backend/tcop/postgres.c           | 2 +-
src/backend/utils/cache/inval.c       | 2 +-
src/backend/utils/cache/typcache.c    | 2 +-
src/bin/pgbench/pgbench.c             | 4 ++--
src/bin/psql/command.c                | 2 +-
src/include/nodes/execnodes.h         | 2 +-
src/include/port.h                    | 2 +-
src/pl/plpython/plpy_elog.c           | 2 +-
15 files changed, 16 insertions(+), 16 deletions(-)