pgsql: Use installcheck-parallel in pg_upgrade's testsuite.

Use installcheck-parallel in pg_upgrade's testsuite.

The installcheck run takes a sizable fraction of test.sh to run. Using
a parallel schedule reduces that noticably.

It's possible that we want to backpatch this at some point, to reduce
buildfarm times, but for now lets just see if this upsets the
buildfarm.

Author: Andres Freund
Discussion: https://postgr.es/m/20181105210039.hh4vvi4vwoq5ba2q@alap3.anarazel.de

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/da906766cd3bef8290db25bd5c8776c03689f3d5

Modified Files
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src/bin/pg_upgrade/test.sh | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)