Fixing the condition to run tests in tempest run

During stestr migration, it  seems like we stopped running the
tests in tempest run cli if config_file or workspace arg are passed.

This commit fixing this behavior.

Change-Id: Idf77ff9dd9c0ba0a134dfe61b1ab79d069d3ff0c
diff --git a/tempest/cmd/run.py b/tempest/cmd/run.py
index 49fb1bc..b8ae2ff 100644
--- a/tempest/cmd/run.py
+++ b/tempest/cmd/run.py
@@ -170,7 +170,7 @@
                 blacklist_file=parsed_args.blacklist_file,
                 black_regex=parsed_args.black_regex)
 
-        elif not (parsed_args.config_file or parsed_args.workspace):
+        else:
             serial = not parsed_args.parallel
             return_code = commands.run_command(
                 filters=regex, subunit_out=parsed_args.subunit,