pgsql: Further buildfarm experience shows that actually we can't run the

Log Message:
-----------
Further buildfarm experience shows that actually we can't run the plancache
test in parallel with the rules test at all, because the former wants to
create a couple of temp views, which can sometimes show up in the latter's
output.  Let's try it in the next parallel group instead.

Modified Files:
--------------
    pgsql/src/test/regress:
        parallel_schedule (r1.40 -> r1.41)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/parallel_schedule.diff?r1=1.40&r2=1.41)