Fix variable type check for valid values in test

Fixes the following errors:
1) **ERROR** Invalid variable type:
valid_values:                            [Blinking] <str>
required_type:                           list
2) **ERROR** Invalid variable type:
valid_values:                            [Off] <str>
required_type:                           list

Change-Id: Ic1c2a1d00951b53e665fe43cac56fdd6e951504b
Signed-off-by: George Keishing <gkeishin@in.ibm.com>
diff --git a/redfish/systems/test_led_indicator_asserted.robot b/redfish/systems/test_led_indicator_asserted.robot
index 4bb201b..2aa7e1e 100755
--- a/redfish/systems/test_led_indicator_asserted.robot
+++ b/redfish/systems/test_led_indicator_asserted.robot
@@ -157,7 +157,7 @@
     ${power_supplies}=  Redfish.Get Attribute  ${REDFISH_CHASSIS_POWER_URI}  PowerSupplies
     Rprint Vars  power_supplies
     FOR  ${power_supply_leds}  IN  @{power_supplies}
-        Valid Value  power_supply_leds['IndicatorLED']  [${expected_indicator_led}]
+        Valid Value  power_supply_leds['IndicatorLED']  ['${expected_indicator_led}']
     END
 
 
@@ -195,7 +195,7 @@
     ${fans}=  Redfish.Get Attribute  ${REDFISH_CHASSIS_THERMAL_URI}  Fans
     Rprint Vars  fans
     FOR  ${fan_leds}  IN  @{fans}
-        Valid Value  fan_leds['IndicatorLED']  [${expected_indicator_led}]
+        Valid Value  fan_leds['IndicatorLED']  ['${expected_indicator_led}']
     END