pgsql: Avoid overflow in MaybeRemoveOldWalSummaries().

Avoid overflow in MaybeRemoveOldWalSummaries().

This commit limits the maximum value of wal_summary_keep_time to
INT_MAX / SECS_PER_MINUTE to avoid overflow when it is converted to
seconds.  In passing, use the HOURS_PER_DAY, MINS_PER_HOUR, and
SECS_PER_MINUTE macros in the code for this GUC instead of hard-
coding those values.

Discussion: https://postgr.es/m/20240314210010.GA3056455%40nathanxps13

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/80686761c49d5194d224b344e968c26981611726

Modified Files
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src/backend/postmaster/walsummarizer.c | 4 ++--
src/backend/utils/misc/guc_tables.c    | 4 ++--
2 files changed, 4 insertions(+), 4 deletions(-)