runUnitTest: log_directory is imported from Unit Tests and thus must be global...

runUnitTest: log_directory is imported from Unit Tests and thus must be global to avoid pylint error.

product/ERP5Type/tests/runUnitTest.py

@@ -713,6 +713,7 @@ def usage(stream, msg=None):
   program = os.path.basename(sys.argv[0])
   print >>stream, __doc__ % {"program": program}
 
+log_directory = None
 def main(argument_list=None):
   if argument_list is None:
     argument_list = []