tests/helper-runtests.sh

run-tests: prevent a (glob) declaration from reordering (?) lines

Previously, if a series of optional output lines marked with '(?)' had a (glob)
in one of the first lines, the output would be reordered such that it came last
if none of the lines were output.  The (re) declaration wasn't affected, which
was helpful in figuring this out.  There were no tests for '(re) (?)' so add
that to make sure everything plays nice.

#
# Avoid interference from actual test env:

unset HGTEST_JOBS
unset HGTEST_TIMEOUT
unset HGTEST_PORT
unset HGTEST_SHELL