pgsql: Remove duplicated words in comments of pgstat.c and pgstat_inter

Remove duplicated words in comments of pgstat.c and pgstat_internal.h

Author: Atsushi Torikoshi
Reviewed-by: Nathan Bossart
Discussion: https://postgr.es/m/d00ddbf29f9d09b3a471e64977560de1@oss.nttdata.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/c9dfe2e83a8dbc30e6992ced01da2f7cfa0f63f3

Modified Files
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src/backend/utils/activity/pgstat.c | 4 ++--
src/include/utils/pgstat_internal.h | 6 +++---
2 files changed, 5 insertions(+), 5 deletions(-)