pgsql: Fix unportable code in pgbench.

Fix unportable code in pgbench.

The buildfarm points out that UINT64_FORMAT might not work with sscanf;
it's calibrated for our printf implementation, which might not agree
with the platform-supplied sscanf. Fall back to just accepting an
unsigned long, which is already more than the documentation promises.

Oversight in e6c3ba7fb; back-patch to v11, as that was.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/1a75c1d0c5d967ea2adcd7129092687cded4e7bf

Modified Files
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src/bin/pgbench/pgbench.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)