Fix test_pytestrunner_start
Fix test_pytestrunner_start

by patching add_pathlist_to_PYTHONPATH. This function first checks
whether PYTHONPATH is set in the actual (!) OS environment and then
changes the passed in env list by either setting or prepending the
pathlist to PYTHONPATH. The test failed if the OS environment in
that the test is run hasn't set PYTHONPATH as in the test, we call
add_pathlist_to_PYTHONPATH with an env list where PYTHONPATH is
already set.

jitseniesen/spyder-unittest