pgsql: Make pg_upgrade's test.sh less chatty.

Make pg_upgrade's test.sh less chatty.

Remove "set -x", and pass "-A trust" to initdb explicitly,
to suppress almost all of the noise this script used to emit
on stderr.

Back-patch of commit eb9812f27 into all active branches.

Discussion: https://postgr.es/m/21766.1558397960@sss.pgh.pa.us
Discussion: https://postgr.es/m/20190722193459.GA14241@alvherre.pgsql

Branch
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REL9_4_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/19f9a5aed9a734ca0904df039c777bba569e0d2c

Modified Files
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contrib/pg_upgrade/test.sh | 10 ++--------
1 file changed, 2 insertions(+), 8 deletions(-)