tests: do not unnecessary mangle test name passed as runner parameter

Otherwise `qubes.tests.run -l` output would not be useful as input for
test list.

qubes/tests/run.py

@@ -351,7 +351,7 @@ def main():
         for name in args.names:
             suite.addTests(
                 [test for test in list_test_cases(alltests)
-                 if (str(test)+'/').startswith(name.replace('.', '/')+'/')])
+                 if (str(test)+'/').startswith(name+'/')])
     else:
         suite.addTests(loader.loadTestsFromName('qubes.tests'))