Make pg_upgrade's test.sh less chatty.

The use of "set -x" to echo a subset of the test's commands might've
been a good idea during development of this test, but it's been stable
for long enough now that the extra output isn't very useful.  Also
our project expectations have been trending towards less output in
non-error cases; the fact that "set -x" produces output on stderr
is particularly annoying from that standpoint.  So get rid of it.

Also, pass "-A trust" to initdb explicitly so that it won't issue
a warning about "trust" being an insecure default.  This matches
what the TAP tests have done for a long time, and again gets rid
of some noise on stderr.

Discussion: https://postgr.es/m/21766.1558397960@sss.pgh.pa.us

src/bin/pg_upgrade/test.sh

@@ -22,7 +22,8 @@ unset MAKELEVEL
 standard_initdb() {
 	# To increase coverage of non-standard segment size and group access
 	# without increasing test runtime, run these tests with a custom setting.
-	"$1" -N --wal-segsize 1 -g
+	# Also, specify "-A trust" explicitly to suppress initdb's warning.
+	"$1" -N --wal-segsize 1 -g -A trust
 	if [ -n "$TEMP_CONFIG" -a -r "$TEMP_CONFIG" ]
 	then
 		cat "$TEMP_CONFIG" >> "$PGDATA/postgresql.conf"
@@ -150,9 +151,6 @@ done
 EXTRA_REGRESS_OPTS="$EXTRA_REGRESS_OPTS --port=$PGPORT"
 export EXTRA_REGRESS_OPTS
 
-# enable echo so the user can see what is being executed
-set -x
-
 standard_initdb "$oldbindir"/initdb
 "$oldbindir"/pg_ctl start -l "$logdir/postmaster1.log" -o "$POSTMASTER_OPTS" -w
 
@@ -256,10 +254,6 @@ esac
 pg_dumpall --no-sync -f "$temp_root"/dump2.sql || pg_dumpall2_status=$?
 pg_ctl -m fast stop
 
-# no need to echo commands anymore
-set +x
-echo
-
 if [ -n "$pg_dumpall2_status" ]; then
 	echo "pg_dumpall of post-upgrade database cluster failed"
 	exit 1