Fix missing import for watchdog test

Resolves  openbmc/openbmc-test-automation#1090

Change-Id: Ic25b85a2f3b1dc4787aab5adff08123e360f18e5
Signed-off-by: George Keishing <gkeishin@in.ibm.com>
diff --git a/extended/test_watchdog.robot b/extended/test_watchdog.robot
index 31381af..5cfe17a 100644
--- a/extended/test_watchdog.robot
+++ b/extended/test_watchdog.robot
@@ -6,6 +6,7 @@
 Resource               ../lib/utils.robot
 Resource               ../lib/resource.txt
 Resource               ../lib/boot_utils.robot
+Resource               ../lib/state_manager.robot
 
 Suite Setup            Watchdog Timer Test Setup
 Suite Teardown         Restore Watchdog Default Setting