pg_dump: Remove "option requires an argument -- j" test

This is really testing getopt more than pg_dump, and what getopt returns
exactly appears to differ based on platform, so remove this test.

Per buildfarm.

src/bin/pg_dump/t/001_basic.pl

@@ -81,11 +81,6 @@ command_fails_like(
 	qr/\Qpg_dump: option --if-exists requires option -c\/--clean\E/,
 	'pg_dump: option --if-exists requires option -c/--clean');
 
-command_fails_like(
-	[ 'pg_dump', '-j' ],
-	qr/\Qpg_dump: option requires an argument -- 'j'\E/,
-	'pg_dump: option requires an argument -- \'j\'');
-
 command_fails_like(
 	[ 'pg_dump', '-j3' ],
 	qr/\Qpg_dump: parallel backup only supported by the directory format\E/,