CI script fix (#937)

Author: sbSteveK

.builder/actions/localhost_test.py

@@ -53,4 +53,4 @@ def run(self, env):
             -Daws.crt.aws_trace_log_per_test \
             -Daws.crt.localhost=true"):
             # Failed
-            actions.append("exit 1")
+            sys.exit(1)