GUI: Fix PEL variable import warning

Fixes the following:

[ WARN ] Imported library '/home/george/sandbox/data/pel_variables.py'
 contains no keywords.

Changes:
     - Change the directive from Library to Variable

Tested:
     - NA

Change-Id: I39e575201353ab9040742e492b22ba41b725c4e2
Signed-off-by: George Keishing <gkeishin@in.ibm.com>
diff --git a/gui/gui_test/logs_menu/test_event_logs_sub_menu.robot b/gui/gui_test/logs_menu/test_event_logs_sub_menu.robot
index 72dd4ad..30f0ff0 100755
--- a/gui/gui_test/logs_menu/test_event_logs_sub_menu.robot
+++ b/gui/gui_test/logs_menu/test_event_logs_sub_menu.robot
@@ -4,7 +4,7 @@
 
 Resource        ../../lib/gui_resource.robot
 Resource        ../../../lib/logging_utils.robot
-Library         ../../../data/pel_variables.py
+Variables       ../../../data/pel_variables.py
 
 Suite Setup     Suite Setup Execution
 Suite Teardown  Suite Teardown Execution