pgsql: Shave some cycles off subscription/t/100_bugs.pl tests.

Shave some cycles off subscription/t/100_bugs.pl tests.

We can re-use the clusters set up for this test script's first test,
instead of generating new ones. On my machine this is good for
about a 20% reduction in this script's runtime, from ~6.5 sec to
~5.2 sec.

This idea could be taken further, but it'd require a much more invasive
patch. These cases are easy because the Perl variable names were
already being re-used.

Anton A. Melnikov

Discussion: https://postgr.es/m/eb7aa992-c2d7-6ce7-4942-0c784231a362@inbox.ru

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/fccaf259f22f4aedc02033516c561ca86903077d

Modified Files
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src/test/subscription/t/100_bugs.pl | 29 ++++++++++++++++++++---------
1 file changed, 20 insertions(+), 9 deletions(-)