Amend suite teardown directive

Changes:
   - Add Run Keyword And Ignore Error  robot keyword to
     prevent suite teardown failure while performing
     redfish session logout.

Tested:
    I ran the test suite redfish/update_service/test_bmc_image_switch.robot
    and it passed.

Change-Id: I42c1b36035e8ad0dbb1f734aa08583a7b09c7a77
Signed-off-by: George Keishing <gkeishin@in.ibm.com>
diff --git a/redfish/update_service/test_bmc_image_switch.robot b/redfish/update_service/test_bmc_image_switch.robot
index 67efb0e..26ee0e5 100755
--- a/redfish/update_service/test_bmc_image_switch.robot
+++ b/redfish/update_service/test_bmc_image_switch.robot
@@ -8,7 +8,7 @@
 Library                  ../../lib/tftp_update_utils.py
 
 Suite Setup              Suite Setup Execution
-Suite Teardown           Redfish.Logout
+Suite Teardown           Run Keyword And Ignore Error  Redfish.Logout
 Test Teardown            FFDC On Test Case Fail
 
 Force Tags    Test_BMC_Image_Switch